In this article:

• Which updates might cause this error?
• How you can work around the error

Due to recent Microsoft .NET Framework Updates released for Windows 10 and Server 2016, some users may experience the error below when running the PC*MILER user interface.

Which updates might cause the error?

The updates below are likely the cause of the Fatal Exception. Microsoft lists Windows Presentation Foundation (WPF) app crashes among its "Known issues."

• February 9, 2021-KB4601050 Cumulative Update for .NET Framework 3.5 and 4.8
• January 26, 2021-KB4598461 Cumulative Update Preview for .NET Framework 3.5, 4.7.2 and 4.8

Known issues in this update:

How you can work around the error

While awaiting a new Microsoft update to resolve the issue, you can uninstall the update if you wish. This would prevent the PC*MILER error from occurring.

To uninstall the update:

1. Select the Windows key on your keyboard
   
2. Type: "appwiz.cpl" and select Enter
   
3. Select View installed updates
   
4. Right-click on the KB4601050, KB4598461, KB4601056, KB4601058, or KB4601051 update.
5. Select Uninstall