System.Windows.Forms.dll cannot be found

Posted on 2012-08-28
Last Modified: 2012-09-12
I get an error from an application that C:\WINDOWS\Microsoft.Net\assembly\GAC_32\System.Windows.Forms\v4.0_4.0.0.0__b77a5c561934e089\System.Windows.Forms.dll cannot be found.

Which software should I install in order not to receive this error ?
Question by:itbabe
    LVL 74

    Expert Comment

    by:käµfm³d 👽
    This is the .NET Framework--version 4.0 if I'm reading the error message correctly.
    LVL 1

    Expert Comment

    kaufmed is correct. You need to install/reinstall .net framework 4.0. The web installer can be found here:

    Author Comment

    They tell me that the dotnet 4.0 software is distributed correctly at the company.
    When I check add remove programs I see the image in the attached screenshot.

    I find a folder called C:\WINDOWS\Microsoft.NET\Framework\v4.0.30319 and a keyname called HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\v4.0.30319.

    But no  C:\WINDOWS\Microsoft.Net\assembly\GAC_32\System.Windows.Forms\v4.0_4.0.0.0__b77a5c561934e089\System.Windows.Forms.dll  file.
    Is there a specific feature that they possibly did not install ?

    Author Comment

    I do find an assembly here :C:\WINDOWS\Microsoft.NET\assembly\GAC_MSIL\System.Windows.Forms\v4.0_4.0.0.0__b77a5c561934e089. , but the application is maybe not looking in the right place?

    Can we configure in any way that the application looks elsewhere for the assembly ?
    LVL 1

    Accepted Solution

    The GAC which stands for Global Assembly Cache. Does not have that directory. Period!
    The dll file you are probably looking for is located here
    If you copy the to the directory where the executable is, that should fix your problem. The developer messed something up I think...

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