Related
I am trying to host a SQL server database, but whenever I try to connect to it I get this error:
The login is from an untrusted domain and cannot be used with Windows
authentication
I am connecting through Matlab using the following command:
conn = database('Clinical_Data','DoyleLab07\Acc','','com.microsoft.sqlserver.jdbc.SQLServerDriver','jdbc:sqlserver://DOYLELAB07\SQLEXPRESS:54287;database=Clinical_Data;integratedSecurity=true;').
Connecting to the database using matlab worked fine as long as I was using matlab on the computer which I was using to host the server. However, when I use another computer and the same Matlab command I get the error I showed above.
When I look under control panel\system. I notice that no domain is listed on my host PC or the PC I am using to connect to the host, but both computers are in the same workgroup. Would I be able to fix my problem by creating a domain and adding the foreign PC and the host to that domain? If so, how can this be accomplished?
Any suggestions will be very much appreciated.
Thank you for reading my post.
Getting rid of Integrated Security=true worked for me.
In order to use Windows Authentication one of two things needs to be true:
You are executing from the same machine as the database server.
You have an Active Directory environment and the user the application is executing under (usually the logged in user) has rights to connect to that database.
If neither of those are true you have to do one of two things:
Establish a Windows Domain Controller, connect all of the relevant machines to that controller, then fix SQL server to use domain accounts; OR,
Change SQL server to use both Windows and SQL Server accounts.
By FAR the easiest way is to change SQL Server to use both Windows and SQL server accounts. Then you just need to create a sql server user on the DB server and change your connection string to do that.
Best case option 1 will take a full day of installation and configuration. Option 2 ought to take about 5 minutes.
If your SQL Server is on one domain controller and you are trying to connect to it from another domain controller then you will get this error when
IntegratedSecurity = true;
This will happen even if you include a valid SQL Server username and password in your connection string as they will automatically be over-written with your windows login and password. Integrated security means simply - use your windows credentials for login verification to SQL Server. So, if you are logged in to a different domain controller then it will fail. In the case where you are on two different domain controllers then you have no choice but to use
IntegratedSecurity = false;
Now, when Integrated security is false SQL Server will use the SQL Server login and password provided in your connection string. For this to work, the SQL Server instance has to have its authentication mode configured to mixed mode, being, SQL Server and Windows Authentication mode.
To verify or change this setting in SQL Server you can open the SQL Server Management Studio and right-click on your server name and then select Properties. On the pop-up that appears select Security and you will see where to alter this setting if you need to.
I've had this same issue when using DNS aliases and hosts files to connect to a machine using a different domain name.
Say you have a SQL server called sql1 on mydomain.com - which is an Active Directory domain - and you also have a DNS zone for mydomain.net, and - for consistency - you set up a DNS alias (CNAME) record for database.mydomain.net --> sql1.mydomain.com
You'll be able to connect to sql1.mydomain.com using Windows integrated security, but won't be able to connect to database.mydomain.net even though it's the same server because the domain name doesn't match your AD domain.
This error message can also occur if the account you are using to access the SQL server is locked out by the domain.
I was facing the issue while connecting to SQL Always On Listener. Disabling the loop back check resolved the issue.
Edit the registry using regedit. (Start –> Run > Regedit )
Navigate to: HKLM\System\CurrentControlSet\Control\LSA
Add a DWORD value called “DisableLoopbackCheck”
Set this value to 1
https://blog.sqlauthority.com/2017/04/18/sql-server-login-failed-login-untrusted-domain-cannot-used-windows-authentication/
Why not use a SQL Server account and pass both the user name and password?
Here is the reason why.
In short, it looks like you have an authentication issue.
The problem with workgroups is there is no common Access Control List like Active Directory (AD). If you are using ODBC or JDBC, the wrong credentials are passed.
Even if you create a local windows account (LWA) on the machine (SE) that has SQL Express installed (SE\LWA), the credentials that will be passed from your client machine (CM) will be CM\LWA.
As mentioned here, you might need to disable the loopback
Loopback check can be removed by adding a registry entry as follows:
Edit the registry using regedit. (Start –> Run > Regedit )
Navigate to: HKLM\System\CurrentControlSet\Control\LSA
Add a DWORD value called “DisableLoopbackCheck” Set this value to 1
If you using windows authentication make sure that password of the user hasn't expired. An expired password can explain this error. This was the problem in my case.
Same Error with Connection String in Visual Studio dev environment
Our development database server was recently given a self-signed certificate so it automatically became untrusted. This resulted in the login error cited above. I added TrustServerCertificate=True to my connection string and it works now.
"Server=TheServerAddress; Database=TheDataBase; User Id=TheUsername; Password=ThePassword; TrustServerCertificate=True"
NOTE: This certificate configuration is not recommended for production environments.
In my case the Aliases within SQL Native Client 11.0 Configuration were pointing to invalid server/IP. Once updated it worked correctly.
To check:
1. Start "SQL Server Configuration Manager"
2. Navigate to "SQL Native Client 11.0 Configuration" and then "Aliases"
3. Ensure "Alias Name" and "Server" match correctly for TCP/IP
Following worked for me to get access from another machine to SQL Server using Windows Authentication. This approach may be useful only in development/test environment. E.g. you need to update password manually once you change it on your working machine.
On machine with SQL Server go to Control Panel and add new Windows User with same username and password as is on your working machine. Then create SQL Server login for this user:
CREATE LOGIN [SQLSERVERHOST\myuser] FROM WINDOWS;
Now you can use this login for Windows Authentication.
If you receive error 'The login is from an untrusted domain', this may mean that you changed password on your working machine and now need to update password on SQL Server machine.
Just adding my suggestion for a resolution, I had a copy of a VM server for developing and testing, I created the database on that with 'sa' having ownership on the db.
I then restored the database onto the live VM server but I was getting the same error mentioned even though the data was still returning correctly. I looked up the 'sa' user mappings and could see it wasn't mapped to the database when I tried to apply the mapping I got a another error "Fix: Cannot use the special principal ‘sa’. Microsoft SQL Server, Error: 15405". so I ran this instead
ALTER AUTHORIZATION ON DATABASE::dbname TO sa
I rechecked the user mappings and it was now assigned to my db and it fixed a lot of access issues for me.
Joining a WORKGROUP then rejoining the domain fixed this issue for me.
I got this error while using Virtual Box VM's. The issue started to happen when I moved the VM files to a new drive location or computer.
Hope this helps the VM folks.
We now use a privileged account management solution that changes our passwords regularly. I ended up receiving this error after my password was changed. Closing and re-opening SSMS with the new password resolved my issue.
I started to get this error when i tried to login to SSMS using 'windows Authentication'. This started to happen after i renamed the Windows SQL server. I tried everything to resolve this error and in my particular case changing the machine names in the 'hosts' file to reflect the name SQL server name change resolved the issue. C:\Windows\System32\Drivers\etc\hosts
I had this problem because we where using a DNS name from an old server, ponting to a new server. Using the newserver\inst1 address, worked. both newserver\inst1 and oldserver\inst1 pointed to the same IP.
Yet another thing to check:We had our nightly QA restore job stop working all of a sudden after another developer remoted into the QA server and tried to start the restore job during the middle of the day, which subsequently failed with the "untrusted domain" message. Somehow the server pointed to be the job's maintenance plan was (changed?) using the ip address, instead of the local machine's name. Upon replacing with the machine name the issue was resolved.
TLDR: Changing the DNS server to the loop back address worked for me.
I am working in VirtualBox and had setup two Windows Server 2016 instances. Server A is configure as a Domain Controller and Server B as an SQL Server. After adding Server B to the domain I cold not connect to with Management Studio from Server A. I was getting the "The login is from an untrusted domain and cannot be used with Windows authentication".
My initial configuration had the server getting its IP from the VirtualBox DHCP server.
I changed this to use static IP and entered the 127.0.0.1 address in the Primary DNS and this worked for me.
Hope this helps someone passing by.
I enabled Trust Server Certificate in the Connection Properties and it worked for me
You might find out that you have more than one connection string, and you forgot to change the other one to Integrated Security to false. It happened to me. This answer might help someone.
I was focusing on the web config and the access rights, after a long hustle i remembered that I have another connection string in one of my classes for the emails, I had to change the connection string on the class to use the web config one.
i removed Integrated Security=true and Trusted_Connection=True both of them , worked for me..
In .net Core also you may get this error if Trusted_Connection=True;
Is set. Sample setting in appsettings.json
ConnectionStrings": {
"DefaultConnection": "Server=serverName; Database=DbName; uid=userId; pwd=password; MultipleActiveResultSets=true"
},
Sometime SSMS hang and close all of sudden ,then you get below error when you reconnect to SSMS
i) The Login is From an Untrusted Domain and Cannot be Used with Windows Authentication
OR
ii) The target principal name is incorrect .Cannot generate SSPI context.
In both cases RESTART YOUR MACHINE.
I also had a similar error but then I realised I just had changed the password for my system which caused this error.
To resolve it , I simply logged out of the current session and logged in again and this time
Please Use This Connection URL It's Work Fine
"Data Source=Your IP Address;Initial Catalog = DatabaseName;User ID =sa;Password =your PassWord;TrustServerCertificate=True"
Example : "Data Source=192.168.150.122;Initial Catalog=StudentDb;User ID=sa; PassWord=123;TrustServerCertificate=True"
If you have two servers on the same domain (eg. APP and DB), you can also use Windows Authentication between the app and MSSQL by setting up local users on both machines that match (same username and password). If you don't have the passwords matched up, it can throw this error.
Following was working for me. hope this helps you
<add name="getconn" connectionString="Data Source=servername;Initial Catalog=DBName;Persist Security Info=True;User ID=sa;Password=***" />
I'm using Entity Core Framework and I keep getting an error when connecting to the SQL Server. Sqlcmd: Error: Microsoft ODBC Driver 17 for SQL Server : Login failed for user 'SA'..
I'm following Microsoft's official series and I'm on the first video and I'm using the second connection string provided by microsoft. The one I'm supposed to use is the second one, but I've used both and neither have worked. After searching the internet I've came to the conclusion that the issue has to do with the connection string, but I've tried many version of the same connection string (double quotes, single quotes, no quotes, etc) and none of them have worked.
Does anybody know why this is happening?
Login failed for user 'sa' means one of four things:
The connection string does not have the right password for the sa account
(You should be setting your own password on that account and expect to change that part of the connection string).
The sa account is disabled on the server.
(This is a best practice. You should disable the built in sa account and have your own admin account instead. Note it's common for vendor products to prohibit this, though :( ).
Sql authentication is not enabled on the server (it's using Windows Authentication).
You're connecting to a different SQL Server instance than expected.
You did reach some SQL Server or the error message would be different, but it might be a different instance than expected, even on the same computer.
I am trying to host a SQL server database, but whenever I try to connect to it I get this error:
The login is from an untrusted domain and cannot be used with Windows
authentication
I am connecting through Matlab using the following command:
conn = database('Clinical_Data','DoyleLab07\Acc','','com.microsoft.sqlserver.jdbc.SQLServerDriver','jdbc:sqlserver://DOYLELAB07\SQLEXPRESS:54287;database=Clinical_Data;integratedSecurity=true;').
Connecting to the database using matlab worked fine as long as I was using matlab on the computer which I was using to host the server. However, when I use another computer and the same Matlab command I get the error I showed above.
When I look under control panel\system. I notice that no domain is listed on my host PC or the PC I am using to connect to the host, but both computers are in the same workgroup. Would I be able to fix my problem by creating a domain and adding the foreign PC and the host to that domain? If so, how can this be accomplished?
Any suggestions will be very much appreciated.
Thank you for reading my post.
Getting rid of Integrated Security=true worked for me.
In order to use Windows Authentication one of two things needs to be true:
You are executing from the same machine as the database server.
You have an Active Directory environment and the user the application is executing under (usually the logged in user) has rights to connect to that database.
If neither of those are true you have to do one of two things:
Establish a Windows Domain Controller, connect all of the relevant machines to that controller, then fix SQL server to use domain accounts; OR,
Change SQL server to use both Windows and SQL Server accounts.
By FAR the easiest way is to change SQL Server to use both Windows and SQL server accounts. Then you just need to create a sql server user on the DB server and change your connection string to do that.
Best case option 1 will take a full day of installation and configuration. Option 2 ought to take about 5 minutes.
If your SQL Server is on one domain controller and you are trying to connect to it from another domain controller then you will get this error when
IntegratedSecurity = true;
This will happen even if you include a valid SQL Server username and password in your connection string as they will automatically be over-written with your windows login and password. Integrated security means simply - use your windows credentials for login verification to SQL Server. So, if you are logged in to a different domain controller then it will fail. In the case where you are on two different domain controllers then you have no choice but to use
IntegratedSecurity = false;
Now, when Integrated security is false SQL Server will use the SQL Server login and password provided in your connection string. For this to work, the SQL Server instance has to have its authentication mode configured to mixed mode, being, SQL Server and Windows Authentication mode.
To verify or change this setting in SQL Server you can open the SQL Server Management Studio and right-click on your server name and then select Properties. On the pop-up that appears select Security and you will see where to alter this setting if you need to.
I've had this same issue when using DNS aliases and hosts files to connect to a machine using a different domain name.
Say you have a SQL server called sql1 on mydomain.com - which is an Active Directory domain - and you also have a DNS zone for mydomain.net, and - for consistency - you set up a DNS alias (CNAME) record for database.mydomain.net --> sql1.mydomain.com
You'll be able to connect to sql1.mydomain.com using Windows integrated security, but won't be able to connect to database.mydomain.net even though it's the same server because the domain name doesn't match your AD domain.
This error message can also occur if the account you are using to access the SQL server is locked out by the domain.
I was facing the issue while connecting to SQL Always On Listener. Disabling the loop back check resolved the issue.
Edit the registry using regedit. (Start –> Run > Regedit )
Navigate to: HKLM\System\CurrentControlSet\Control\LSA
Add a DWORD value called “DisableLoopbackCheck”
Set this value to 1
https://blog.sqlauthority.com/2017/04/18/sql-server-login-failed-login-untrusted-domain-cannot-used-windows-authentication/
Why not use a SQL Server account and pass both the user name and password?
Here is the reason why.
In short, it looks like you have an authentication issue.
The problem with workgroups is there is no common Access Control List like Active Directory (AD). If you are using ODBC or JDBC, the wrong credentials are passed.
Even if you create a local windows account (LWA) on the machine (SE) that has SQL Express installed (SE\LWA), the credentials that will be passed from your client machine (CM) will be CM\LWA.
As mentioned here, you might need to disable the loopback
Loopback check can be removed by adding a registry entry as follows:
Edit the registry using regedit. (Start –> Run > Regedit )
Navigate to: HKLM\System\CurrentControlSet\Control\LSA
Add a DWORD value called “DisableLoopbackCheck” Set this value to 1
If you using windows authentication make sure that password of the user hasn't expired. An expired password can explain this error. This was the problem in my case.
Same Error with Connection String in Visual Studio dev environment
Our development database server was recently given a self-signed certificate so it automatically became untrusted. This resulted in the login error cited above. I added TrustServerCertificate=True to my connection string and it works now.
"Server=TheServerAddress; Database=TheDataBase; User Id=TheUsername; Password=ThePassword; TrustServerCertificate=True"
NOTE: This certificate configuration is not recommended for production environments.
In my case the Aliases within SQL Native Client 11.0 Configuration were pointing to invalid server/IP. Once updated it worked correctly.
To check:
1. Start "SQL Server Configuration Manager"
2. Navigate to "SQL Native Client 11.0 Configuration" and then "Aliases"
3. Ensure "Alias Name" and "Server" match correctly for TCP/IP
Following worked for me to get access from another machine to SQL Server using Windows Authentication. This approach may be useful only in development/test environment. E.g. you need to update password manually once you change it on your working machine.
On machine with SQL Server go to Control Panel and add new Windows User with same username and password as is on your working machine. Then create SQL Server login for this user:
CREATE LOGIN [SQLSERVERHOST\myuser] FROM WINDOWS;
Now you can use this login for Windows Authentication.
If you receive error 'The login is from an untrusted domain', this may mean that you changed password on your working machine and now need to update password on SQL Server machine.
Just adding my suggestion for a resolution, I had a copy of a VM server for developing and testing, I created the database on that with 'sa' having ownership on the db.
I then restored the database onto the live VM server but I was getting the same error mentioned even though the data was still returning correctly. I looked up the 'sa' user mappings and could see it wasn't mapped to the database when I tried to apply the mapping I got a another error "Fix: Cannot use the special principal ‘sa’. Microsoft SQL Server, Error: 15405". so I ran this instead
ALTER AUTHORIZATION ON DATABASE::dbname TO sa
I rechecked the user mappings and it was now assigned to my db and it fixed a lot of access issues for me.
Joining a WORKGROUP then rejoining the domain fixed this issue for me.
I got this error while using Virtual Box VM's. The issue started to happen when I moved the VM files to a new drive location or computer.
Hope this helps the VM folks.
We now use a privileged account management solution that changes our passwords regularly. I ended up receiving this error after my password was changed. Closing and re-opening SSMS with the new password resolved my issue.
I started to get this error when i tried to login to SSMS using 'windows Authentication'. This started to happen after i renamed the Windows SQL server. I tried everything to resolve this error and in my particular case changing the machine names in the 'hosts' file to reflect the name SQL server name change resolved the issue. C:\Windows\System32\Drivers\etc\hosts
I had this problem because we where using a DNS name from an old server, ponting to a new server. Using the newserver\inst1 address, worked. both newserver\inst1 and oldserver\inst1 pointed to the same IP.
Yet another thing to check:We had our nightly QA restore job stop working all of a sudden after another developer remoted into the QA server and tried to start the restore job during the middle of the day, which subsequently failed with the "untrusted domain" message. Somehow the server pointed to be the job's maintenance plan was (changed?) using the ip address, instead of the local machine's name. Upon replacing with the machine name the issue was resolved.
TLDR: Changing the DNS server to the loop back address worked for me.
I am working in VirtualBox and had setup two Windows Server 2016 instances. Server A is configure as a Domain Controller and Server B as an SQL Server. After adding Server B to the domain I cold not connect to with Management Studio from Server A. I was getting the "The login is from an untrusted domain and cannot be used with Windows authentication".
My initial configuration had the server getting its IP from the VirtualBox DHCP server.
I changed this to use static IP and entered the 127.0.0.1 address in the Primary DNS and this worked for me.
Hope this helps someone passing by.
I enabled Trust Server Certificate in the Connection Properties and it worked for me
You might find out that you have more than one connection string, and you forgot to change the other one to Integrated Security to false. It happened to me. This answer might help someone.
I was focusing on the web config and the access rights, after a long hustle i remembered that I have another connection string in one of my classes for the emails, I had to change the connection string on the class to use the web config one.
i removed Integrated Security=true and Trusted_Connection=True both of them , worked for me..
In .net Core also you may get this error if Trusted_Connection=True;
Is set. Sample setting in appsettings.json
ConnectionStrings": {
"DefaultConnection": "Server=serverName; Database=DbName; uid=userId; pwd=password; MultipleActiveResultSets=true"
},
Sometime SSMS hang and close all of sudden ,then you get below error when you reconnect to SSMS
i) The Login is From an Untrusted Domain and Cannot be Used with Windows Authentication
OR
ii) The target principal name is incorrect .Cannot generate SSPI context.
In both cases RESTART YOUR MACHINE.
I also had a similar error but then I realised I just had changed the password for my system which caused this error.
To resolve it , I simply logged out of the current session and logged in again and this time
Please Use This Connection URL It's Work Fine
"Data Source=Your IP Address;Initial Catalog = DatabaseName;User ID =sa;Password =your PassWord;TrustServerCertificate=True"
Example : "Data Source=192.168.150.122;Initial Catalog=StudentDb;User ID=sa; PassWord=123;TrustServerCertificate=True"
If you have two servers on the same domain (eg. APP and DB), you can also use Windows Authentication between the app and MSSQL by setting up local users on both machines that match (same username and password). If you don't have the passwords matched up, it can throw this error.
Following was working for me. hope this helps you
<add name="getconn" connectionString="Data Source=servername;Initial Catalog=DBName;Persist Security Info=True;User ID=sa;Password=***" />
I'm new to SQL related matters so please bare with my lack of knowledge and asking a question which has been asked countless times before.
I have to connect to a SQL database server which is located at a remote location at xxx.xx.xxx.xx:3306, but every time I try to connect I get the same error:
"A network-related or instance-specific error occurred while establishing a connection to SQL server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: TCP Provider, error: 0 - No connection could be made because the target machine actively refused it.)"
I get this same error whether I try to connect using SQL Server Management Studio or in a C# program via:
SqlConnection myConnection = new SqlConnection(...)
myConnection.Open();
I've tried it on two different computers, both on the same home network. I've had a look at the SQL server configuration manager on the computer which I installed SQL Server on, enabling TCP/IP and fiddling with the port values settings, but I'm guessing this is just for configuring an SQL server on my computer and irrelevant to connecting to a remote one. I shouldn't even need to install SQL server to do queries on a remote server anyway, right?
I've turned off my Windows firewall and my router firewall, though ShieldsUP still says
Port: 3306
Status: Stealth
Your system has achieved a perfect "TruStealth" rating. Not a single packet — solicited or otherwise — was received from your system as a result of our security probing tests. Your system ignored and refused to reply to repeated Pings (ICMP Echo Requests). From the standpoint of the passing probes of any hacker, this machine does not exist on the Internet. Some questionable personal security systems expose their users by attempting to "counter-probe the prober", thus revealing themselves. But your system wisely remained silent in every way. Very nice.
I read that this is irrelevant as well, since I'm not the one hosting the server, but when I was given the address, I was given the port as well, so I must have to do something with it. I'm just not sure what. My understanding of ports really is quite shaky.
I've been trying this for over a day now, and I can't think of anything more I can do.
EDIT: I fixed the problem. I had to use MySQL, not MSSQL. Doh. Sorry guys.
If you are sure the remote SQL Server is running on port 3306 (otherwise I'm not sure why you talked in the question about that port specifically), try the following connection string:
user id=username; password=password;
data source=123.45.678.90,3306;
initial catalog=dbname;
Network Library=dbmssocn;
I think without the port you'll have trouble if the other end has disabled the SQL Browser service. You should also make sure it isn't a named instance, in which case you may need:
user id=username; password=password;
data source=123.45.678.90\InstaneName,3306;
initial catalog=dbname;
Network Library=dbmssocn;
First of all the database is local or distant ?
The you have to ensure that your connection string is well written.
Here's an example of a valid connection string :
Data Source=myServerAddress;Initial Catalog=myDataBase;User Id=myUsername;Password=myPassword;
More about connection strings :
Connection Strings
Now if everything is set up correctly you have to enable remote connections to SQL Server on the host. To do so please refer to this article :
Enable SQL Server Remote Connections
Just go to ypur serveices and check whether your SQL Server (MSSQLSERVER) is running.Most of the time this error happens when SQL Server (MSSQLSERVER) is stopped.
Then select it right click and click start.problem solved !!!
Sorry if this is the most seen question on the web, but this is my turn. I am trying to publish my asp.net mvc app on IIS 7 under MS Sql Server 2008. I am on a Windows Server 2008 virtual machine. I get the following classical error:
A network-related or instance-specific
error occurred while establishing a
connection to SQL Server. The server
was not found or was not accessible.
Verify that the instance name is
correct and that SQL Server is
configured to allow remote
connections. (provider: SQL Network
Interfaces, error: 26 - Error Locating
Server/Instance Specified)
Under SQLServer, Allow remote connections is checked. My connection string is:
Data Source=.\MSSQLSERVER;Initial Catalog=mydbname;User Id=sa;Password=mypassword
I also tried with no username/password and "Integrated Security=true". There is only one instance of SQLServer installed.
I tried to access my web page locally and remotely. There is no active firewall on the virtual machine.
Make sure you have TCP/IP set up as a transport in your SQL Server configuration tool.
Thanks guys for the try. I found the solution and it is related to an info that I forgot to give. I hope it can help someone as new as me on these things.
I use NHibernate, and the connection string is actually in the nhibernate.cfg.xml file. The one in the web.config file is actually used by my various providers (users/roles). I fixed that by removing the connection string from the NH config file. I now retrieve it with:
string connectionString = ConfigurationManager.
ConnectionStrings["myConnectString"].ConnectionString;
and I set it in NH with:
Configuration cfg = new Configuration();
cfg.Configure(cfgFile);
cfg.SetProperty(NHibernate.Cfg.Environment.ConnectionString, connectionString);
Now I get:
Cannot open database "mydb"
requested by the login. The login
failed. Login failed for user 'NT
AUTHORITY\NETWORK SERVICE'.
But this is another story, for another question if I can't find the answer.
PS: I had to use "." as the server name otherwise .\MSSQLSERVER was producing a new error "invalid connection string". Thx Ian and Jared for the tip.
is that the actual data source line from the web config?
If so then it's should be in quotes of course, for safety add a ; on the end and check that is the actual name of your instance, you can check windows services for your instance name.
try substituting localhost instead of . and can you connect from sql server management studio using the credentials in your connection string?
As mentioned by Robert, try:
ConnectionString="Data Source=(LOCAL)\MSSQLSERVER;Initial Catalog=mydbname;User ID=sa;Password=mypassword"
I'm not sure if connection strings are case sensitve, but I notice that you have 'Id' instead of 'ID'.
Edit:
Am not sure if you need \MSSQLSERVER?
are you sure it's a named instance of SQL?
try
Data Source=.;Initial Catalog=mydbname;User Id=sa;Password=mypassword
UPDATE:
from this site
did you try the following:
Make sure the server machine is reachable, e.g, DNS can be resolve correctly, you are able to ping the server (not always true).
Make sure SQL Browser service is running on the server.
If firewall is enabled on the server, you need to put sqlbrowser.exe and/or UDP port 1434 into exception.
Well I am facing the same above issue since morning (past 8 hours) did lots of stuff like create a Domain Name, setup a new application pool identity but nothing worked :(
I just made a small changes in web.config file for connection string that is:
Integrated Security=False instead of True... and now it is working perfectly