Unable to add new DLLs in a PDM 2020 add-in

I'm trying to add a new DLL on my PDM 2020 add-in and can't do it. I get the following error message: The archive server cannot open the Windows registry.

Has anyone ever encountered this problem?

I tried with an administrator login, same message. On the archive server, the same message.

The DLL is built in Framework 4.5.0

Thank you for your reactions.

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