Adding Data to a table with Visual Studio - sql-server

Question

I want to add data to my App table in Visual Studio. When I run the program, I fill the information into the text boxes, and when I click the add button, I receive this message from this code:
"Cmd.ExecuteNONQuerry" : An unhandled exception of type
'System.Data.SqlClient.SqlException' occurred in System.Data.dll
When I run "Build Solution" I receive this:
========== Build: 0 succeeded, 0 failed, 1 up-to-date, 0 skipped ==========
Can somebody please help me.
Imports System.Data.SqlClient
Public Class APP
Dim Con As New SqlConnection
Private Sub Button1_Click(sender As Object, e As EventArgs) Handles ButtonAdd.Click
Con.Open()
Dim Cmd As New SqlCommand(("INSERT INTO App VALUES('" & _
ID.Text & "','" & _
Dat.Text & "','" & _
Inst.Text & "', '" & _
Credent.Text & "', '" & _
AppOwner.Text & "', '" & _
Status.Text & "', '" & _
SerialNr.Text & "', '" & _
MAC.Text & "', '" & _
DellNr.Text & "', '" & _
Model.Text & "', '" & _
Description.Text & _
"', '" & Service.Text & _
"', '" & Indkøbt.Text & "',)"), Con)
Cmd.ExecuteNonQuery()
Con.Close()
MsgBox("Success....", MsgBoxStyle.Information, "SUCCESS")
ID.Clear()
Dat.Clear()
Inst.Clear()
Credent.Clear()
AppOwner.Clear()
Status.Clear()
SerialNr.Clear()
MAC.Clear()
DellNr.Clear()
Model.Clear()
Description.Clear()
Service.Clear()
Indkøbt.Clear()
ID.Focus()
End Sub
Private Sub Form1_Load(sender As Object, e As EventArgs) Handles MyBase.Load
Con.ConnectionString = "Data Source=BYG-A101-MOELKA;Initial Catalog=App;Integrated Security=True"
End Sub

Answer 1

At the first glance:
"', '" & Indkøbt.Text & "',)"), Con)
is wrong, it should be
"', '" & Indkøbt.Text & "')"), Con)
But there is another big Problem: you are not using sqlparameters, so your code will crash if someone enters a "'".
When using an insert like you do, it´s also ... more readable if you also specify the field list to see, if you inserting values in the correct databasefield. But much better change to sqlparameters.
Addition - SQL Parameters (with an update Statement, but the principle should be clear):
sqlStmt = "UPDATE table SET fieldname = #fieldparameter WHERE ..."
Using sqlComm As New SqlCommand(sqlStmt, sqlConn)
sqlComm.Parameters.Add(New SqlParameter("#fieldparameter", yourvalue))
sqlComm.ExecuteNonQuery()
End Using