De-install custom python (The User-specified library ...python37.dll could not be loaded)

  • 29 May 2024
  • 1 reply

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  • Contributor
  • 55 replies

We used to need custom python on FME-Server. I’m no system administrator, but I had found out how to install it (Using Python with FME Flow (

Now we updated to FMEFlow 2024 and we don’t need custom python anymore, so I didn’t install it. but obviously it is still registered somewhere that we used to need a different python.dll, for I get the warning “The User-specified library ...python37.dll could not be loaded”. 

How can I reset everything to default-settings? I tried it with this: 

<FMEFlowDir>Server/fme/fme.exe APPLY_SETTINGS SYSTEM "Python/Use Custom Python 64" false

and restartet the FMEServer-services, but the warning remains in the log.

Thanks, Vera



I ran this command as well to reset to the standard python.dll:

<FMEFlowDir>Server/fme/fme.exe APPLY_SETTINGS SYSTEM "Python/Python Interpreter 64" "C:\Program Files\FMEFlow\Server\fme\fmepython312\python312.dll"

Now I get this warning:

The PYTHONHOME `...' for the user-specified Python interpreter set through FME Options or a PYTHONHOME environment variable does not exist. The user-specified Python interpreter will be used without PYTHONHOME defined, which may cause undefined behavior.

There’s a third command in the above instruction, but I don’t want to set a Custom Python Home, but to get rid of any custom python settings...

<FMEFlowDir>Server/fme/fme.exe APPLY_SETTINGS SYSTEM "Python/Custom Python Home 64" c:/<path_to_python_home>


1 reply

Userlevel 2
Badge +25

The environment variable PYTHONHOME is always present with Python, not just for custom installations.

Try and recreate it.