Error While Loading pyRevit – IronPython TypeLoadException in Revit 2023

[drashti_barot]

I encountered an error while reinstalling and loading pyrevit. Please find the details below:

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Error Title:

pyrevitloader – Ironpython TypeloadException: Could not load type System.Resources.NeutralResourcesLanguageAttribute

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Error Details:

• Source: pyRevit (IronPython engine)

• File Traceback:

  C:\Users\<User>\AppData\Roaming\pyRevit-Master\bin\engines\pyRevitLoader.py C:\Users\<User>\AppData\Roaming\pyRevit-Master\pyrevitlib\pyrevit\__init__.py C:\Users\<User>\AppData\Roaming\pyRevit-Master\pyrevitlib\pyrevit\framework.py

• Error Message:

  SystemError: Could not load type 'System.Resources.NeutralResourcesLanguageAttribute' from assembly 'System.Runtime, Version=4.0.0.0, Culture=neutral, PublicKeyToken=b03f5f7f11d50a3a'.

• Script Executor Traceback (Key Part):

  System.TypeLoadException: Could not load type 'System.Resources.NeutralResourcesLanguageAttribute' from assembly 'System.Runtime, Version=4.0.0.0, Culture=neutral'.

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Possible Cause:

IronPython failed to resolve a .NET Framework class (NeutralResourcesLanguageAttribute) from the System.Runtime.dll assembly.
This typically occurs when the .NET Framework 4.7/4.8 runtime is missing or corrupted, or due to a mismatch between pyRevit’s IronPython engine and the installed .NET libraries.

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Request:
Could you please review this issue and advise on the recommended steps (repairing .NET Framework / switching to CPython engine / clean reinstall of pyRevit)?