“csc.exe – Application Error” when Shutting Windows with a Running .NET Application

Recently, a friend reported to me that my application written in .NET prevents his computer from shutting down. If the application is running when Windows tries to shut down, the following error message appears and Windows cannot shut down:

csc.exe – Application Error

The application failed to initialize properly (0xc0000142). 
Click on OK to terminate the application.

Some investigation reveals that the issue has to do with the .NET class XmlSerializer. My application stores user data into an XML file, which gets saved when the application is closed. In particular, the following code seems to cause the problem:

Dim serializer As New XmlSerializer(ConfigObj.GetType())
Dim writer As New StreamWriter(datafile)
serializer.Serialize(writer, ConfigObj)
writer.Close()

The error occurs as soon as XmlSerializer.Serialize() is called. A file system monitor tool such as Process Monitor shows me that csc.exe is creating temporary files in C:WindowsTemp, which is perhaps interrupted by the shutdown process, causing the above problem. I am not even sure why csc.exe (the Microsoft C# compiler) gets called even though I am using VB.NET!

Not sure how to fix the problem, I have to avoid calling XmlSerializer when Windows is shutting down by using:

Private Sub Form1_FormClosing(ByVal sender As Object, _
ByVal e As System.Windows.Forms.FormClosingEventArgs) Handles Me.FormClosing
…

If e.CloseReason <> CloseReason.WindowsShutDown 

   Dim serializer As New XmlSerializer(ConfigObj.GetType())
   Dim writer As New StreamWriter(datafile)
   serializer.Serialize(writer, ConfigObj)
   writer.Close()

End If
… 

End Sub

This way, user data may be lost, but at least my application does not prevent the system from shutting down. I have to find another way to save user data more frequently…

Reference

• Problem with CSC.EXE