Application crash after moving from .NET 3.5 to .NET 4.0

Question

Recently I upgraded .NET from 3.5 to 4.0 in my desktop application. On my development machine it works fine.

On some production machines it crashes right at start.

1. Windows 8.1, Windows 7

   Problem Event Name: APPCRASH
   Application Name: myApp.exe
   Application Version: 2.0.0.0
   Application Timestamp: 553a56e8
   Fault Module Name: KERNELBASE.dll
   Fault Module Version: 6.3.9600.17415
   Fault Module Timestamp: 54504ade
   Exception Code: e0434f4d
   Exception Offset: 00014598
   OS Version: 6.3.9600.2.0.0.256.4
   Locale ID: 1045

2. Windows XP SP3 with .NET 4.0

Faulting application myApp.exe, version 2.0.0.0, stamp 553a56e8, faulting module kernel32.dll, version 5.1.2600.6532, stamp 53203b53, debug? 0, fault address 0x00012fd3.

Please note that the source is .NET Runtime 2.0 Error. Why?

The application is compiled in .NET 4.0, which is installed on the machine.

Another (much smaller and simpler) application from this solution, which is also compiled for .NET 4.0 works fine.

Any ideas?

Answer 1

You have to change the runtime .NET version in file App.config/web.config to:

<startup>
    <supportedRuntime version="v4.0" sku=".NETFramework,Version=v4.0"/>
</startup>