2 Replies Latest reply on Mar 22, 2018 10:29 AM by John Huntington

    PDM 'Failed to load add-in mscoree.dll' Error

    Kyle Rosenquist

      After logging into EPDM and either right-clicking to load the custom add-in menus, or loading a data card, I get the following error: "Failed to load add-in mscoree.dll. Reason: Class not registered".


      I have tried removing all custom add-ins, repairing and uninstall/reinstalling PDM with no luck. Since mscoree.dll appears to be .NET Framework related, I tried repairing all of these installs as well. None of our other PDM users get this error, so I'm fairly certain it's something on my machine only. Any suggestions on what to try next?




        • Re: PDM 'Failed to load add-in mscoree.dll' Error
          Richard Bremmer

          Try the .net repair tool

          Log on a Windows session with a local administrator account.


          A) Uninstall all .Net FrameWorks (from 1 to latest in reverse order) from Programs and Features > Uninstall. Try uninstalling .Net from latest version to older version.

          Go to Control Panel > Programs and Features > click 'Turn Windows features on or off' > uncheck 'Microsoft .Net Framework 3.5.1' and 'Microsoft .Net Framework 4.6'> ok

          Download .net cleanup utility (dotnetfx_cleanup_tool.zip) from following site:




          Unzip it >Run cleanup_tool.exe >In dialog Products to cleanup: .net Frameworks – All versions >select ‘Cleanup Now’.


          C) Restart computer

          E) Go to Control Panel > Programs and Features > click 'Turn Windows features on or off' > check 'Microsoft .Net Framework 3.5.1'  and 'Microsoft .Net Framework 4.6'> ok

          E) Restart computer and reconfirm behavior.


          There is also a command than compiles all pending .net assemblies. It's something like this "c:\Windows\Microsoft.NET\Framework\v2.0.50727\ngen executeQueuedItems"

          I believe you need to do this for all installed .net versions.


          If that doesn't work your probably best of reinstalling the OS. Finding the cause of .net errors might cost more time.

          • Re: PDM 'Failed to load add-in mscoree.dll' Error
            John Huntington

            What version are you using?  In 2016 or 2015 whenever they integrated PDM profession with the install I was having DLL errors when I tried to load PDM on a contributor machine, not even my VAR figured it out.  But once I installed the full version of solidworks it registered the DLLs and I was able to use PDM. 


            I will say I have installed PDM 2018sp1 for a contributor today without installing Solidworks and it worked just fine


            Other option, register the DLL yourself

            Locate the DLL

            Open the Run command (Windows R)

            type in "regsvr32" (Without quotations)

            drag and drop the DLL into the run command next to the regsvr32

            click OK