Additionally a window opens saying that the standard mail application is not defined. I checked in the system preferences and switched the default mail app from the windows 10 Mail app to Outlook but the error remains.
Any ideas how to debug that?
Thanks for the hint, this made me search in the right place. The answer is pretty simple: I tried to access 32 bit Outlook from 64 bit python. Sorry for the noise.
Glad to hear that your issue has been resolved. I would suggest you mark the helpful reply or your solution to close the thread. If you have any other issue, please feel free to post threads to let us know.