Hi @Julian Clemens ,
What's the version of Excel for Mac are you using? I suggest you go to Excel- About Excel and check the version information:
Make sure the Excel for Mac is up-to date on Mac OS.
Then you can go to Go to Excel- Preferences- Privacy and make sure Connected Serves is enabled.
Just checking in to see if the information was helpful. Please let us know if you would like further assistance.
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