I am testing my application (Windows 7, WinForms, Infragistics controls, C#, .Net 3.5).
I have two monitors and my application saves and restores forms' position on the first or second monitors. So I physically switched off second monitor and disabled it at Screen Resolution on the windows display settings form. I need to know it is possible for my application to restore windows positions (for those windows that were saved on the second monitor) to the first one.
I switched off second monitor and press Detect to apply hardware changes.
Then Windows switched OFF the first monitor for a few seconds to apply new settings. When the first monitor screen came back, my application became unresponsive. My application was launched in debug mode, so I tried to navigate via stack and threads (Visual Studio 2008), paused application, started and did not find any thing that help me to understand why my application is not responsive. Could somebody help my how to detect the source of issue.
Download the Debugging Tools For Windows then run adplus in hang mode. The with the resulting .dmp file open in windbg and invoke:
!analyze -v -hang
You should provide more information about what you saw in the call stack and threads windows. Which threads were running? Did you see anything that was waiting in a sleep or join? Have you tried naming your threads so that it's clearer as to what's going on when you pause (though not necessary since you can get this info from the call stack anyway... it's a convenience thing).
Related
Observed behaviour (everything here is on Windows 10):
I run Visual Studio (tried 13 and 15, both behave the same) logged into user A
After starting up, VS takes virtually no CPU time (<1%)
I log into user B, without signing out of A
VS imediately starts using A LOT of CPU time (~25% on my 4 cores with hyper threading)
I can go back and forth between A and B, and it goes back and forth between low and high CPU usage
This is all without any projects or files opened, though it also happens in that case.
I noticed this because I was originally investigating similar behaviour of a WPF application (after a user reported this issue).
While trying to isolate the problem, I found that even a completely new WPF project, with just a single empty window, behaves exactly the same (whether or not run through Visual Studio).
Through profiling and debugging I found that the app seems to spend a huge amount of time handling windows messages.
Specifically I found that it seems to be almost exclusively WM_PAINT messages (we are talking easily hundreds or thousands of messages per second - as many as the CPU can handle it seems).
No other programs I have running (chrome, skype, sublime text, ..) behaves this way.
Has anybody else seen this kind of behaviour?
And/or any ideas what could cause this, or how I could investigate this further?
Naturally, I cannot fix Visual Studio (unless the problem is with my setup somehow) but I hope there is something I can do about my WPF application.
As per Hans Passant's suggestion in the comments, I reported this problem to Microsoft here:
http://connect.microsoft.com/VisualStudio/feedback/details/2390593/wpf-apps-use-a-lot-of-cpu-time-when-logged-into-different-user
As it turns out this indeed seems to have been a bug in WPF, which is fixed in the current version of Windows 10 (probably specifically since the Anniversary Update (version 1607)).
Hence the solution: Make sure to update your OS.
A WinForms program I have developed prints fine and as expected when run as an interactive user. Using the same account but as a scheduled task, the process will run correctly however it prints part of the output in the incorrect font.
The program is a label printer that prints updated pricing labels. It has an option (-s) that the Task Scheduler calls which does not present the GUI but does an update and prints. Executing this as an interactive user through run works correctly (i.e. the correct font is used).
Any clues as to what's happening here? The font that isn't printing correctly is a non-standard system font.
This runs on a server and I thought it might be due to printer redirection but I did a console logon and it worked fine as an interactive process on the console just as it does as interactive through remote desktop.
Interesting problem. Presumably, Windows doesn't load fonts into the non-interactive logon sessions in order to conserve resources.
See this answer for one approach, using the ps tool to create an interactive session when running the task.
I had a very similar issue to yours (running an application through a scheduled task would use the default font but when running locally it would find the custom font I installed) and I found a solution; On Server 2008, there is an issue where custom fonts are not registered immediately after installing for non-interactive users, whereas regular users (i.e. when running on a user actually logged in to the machine) do have the font registered immediately.
The solution that worked for me was to simply restart the machine the font was installed on and the font started working under the non-interactive accounts, as when the computer is turned on it registers correctly. It appears the font installation has a bug where it doesn't register the font correctly for non-interactive users until a reboot.
Here is the situation. The company I work for builds this piece of software in c that can make a Windows computer act a bit like a TV. Essentially, our piece of software is meant to be played full screen and content is displayed from the internet without the user having to ever touch the computer again.
The problem is that once in a while, the system brings up pop-ups like "Your Windows system is ready for an upgrade." or "Please renew your Norton subscription" etc. which the user has to periodically and manually remove.
Is there a way to display content full screen without being bothered by those warnings?
Yah, whether or not the development community agrees, Microsoft has several standards for when and why it might be acceptable to have exclusive use of the monitor.
The most official strategy is to use DirectX in exclusive mode. This is what games do, what windows media player does in full screen video with hardware acceleration enabled, etc... If your application is multimedia intensive (as suggested by TV like functionality), you should probably be using DirectX too. Besides giving you the exclusive display access it will also increase your applications performance while lowering the CPU load (as it will overload graphics work to the video card when possible).
If DirectX is not an option, there are a great number of hacks available that seem to all behave differently between various generations of windows operating systems. So you might have to be prepared to implement several techniques to cover each OS you plan to support.
One technique is to set your application as the currently running screensaver. A screensaver if really just an EXE renamed to SCR with certain command line switches it should support. But you can write your own application to be such a screensaver and a little launcher stub that sets it as the screensaver and launches it. Upon exit the application should return the original screensaver settings (perhaps the launcher waits for the process to exit so that it returns the settings in both graceful exits and any unplanned process terminations ie: app crash). I'm not sure if this behavior is consistent across platforms though, you'll have to test it.
Preventing other applications from creating window handles is truly a hack in my opinion and pretty bad one that I wouldn't appreciate as a customer of such software.
A constant BringWindowToTop() call to keep you in front is better (it doesn't break other software) but still a little hack-ish.
Catch window creation messages with a global hook. This way you can close or hide unwanted windows before they become visible.
EDIT: If you definitely want to avoid hooks, then you can call a function periodically, which puts your window to the top of the z-stack.
You could disable system updates http://support.microsoft.com/kb/901037 and remove the norton malware.
You could also connect a second screen so that the bubbles appear in the the first monitor.
Or you rewrite it for linux or windows ce.
One final option is to install software that reconfigures your os into a kiosk http://shop.inteset.com/Products/9-securelockdown.aspx
If you don't need keyboard or mouse input, how about running your application as a screensaver?
A lot of thoses messages are trigged/managed by Windows Explorer.
Just replace it with your dummy c#/winform.
By changing the registry value
[HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Winlogon]
"Shell"="Explorer.exe"
You can specify virtually any exe as an alternative to explorer.exe
That's the way all windows based (embedded) system (ATM & co) do.
There's still few adjustment (disable services you dont need / dr watson & others), and of course, you'll want to keep a "restart explorer.exe" backdoor.
But that's a good start
I'm not sure if this is technically a Kiosk, but it's basically the same idea. I have a program that runs full screen all the time from boot to shutdown to control a machine that the computer is hooked to.
Right now I just have a shortcut to the exe in the Startup folder so it starts when the system boots up and logs in. Is there any better way to do this? I'd really like the user to never see the Windows environment (just the windows loading progress bar on boot) if at all possible, but I'm guessing that's not possible.
Just thought I'd ask and see if there is a better way to do this than putting it in the startup folder?
The best option is to use Windows Embedded. This gives you much more control over the shell, and what is run and installed with the system.
If you have to do this with a consumer OS, you can try to bypass the login prompts to auto-login your user, and have your program setup in the registry to startup. Disable any other services you don't need. That will minimize the time the shell is displayed (but it's very difficult to remove it).
i have a WPF application that sits on top of all other windows. 99% of the time it works perfectly however if i dial into my computer from another location using remote desktop and then close the connection and go back to the original computer, my application is not visible. checking the running processes i can see that it is still running however its not visible at all. I assume it has something to do with the remoting but i was wondering if there is some code i can run say every 20 seconds that sits on its own thread that checks whether it is visible and if not will execute some code whether by pInvoke or .NET to become visible again. Any ideas?
Make sure to upgrade to .NET 3.5sp1. There were some changes with remoting which lead to WPF applications being sent as bitmaps in remote desktop in all situations.
In earlier versions of the framework, there were problems with WPF applications causing very odd behavior when combined with remote desktop.
Another idea - make sure you're using the latest and greatest versions of your graphics drivers from your graphics card vendor. WPF makes heavy use of DirectX, and this could potentially be a driver bug preventing the context from resetting appropriately.