Hi @Nikolaus Haminger ,
By default, external Python and R scripts only have read access permission to their working directories.
If your Python or R scripts need access to any other directory, you need give either Read & execute and/or Write permissions to the NT Service\MSSQLLaunchpad service user account and ALL APPLICATION PACKAGES on this directory.
Follow the steps below to grant access.
1.In File Explorer, right click on the folder you want to use as working directory, and select Properties.
2.Select Security and click Edit... to change permissions.
3.Click Add...
4.Make sure the From this location is the local computer name.
5.Enter ALL APPLICATION PACKAGES in Enter the object names to select and click Check Names. Click OK.
6.Select Read & execute under the Allow column.
7.Select Write under the Allow column, if you want to grant write permissions.
8.Click OK and OK.
Refer to this MS document.
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