Authenticate

@Peter Sebastian (Seb) Harrison , Thanks for posting in Q&A. From your description, it seems you are using Microsoft 365 and it has authentication issue now. If there's any misunderstanding, feel free to let us know.

If yes, I suggest to submit new thread in the following Microsoft 365 forum to get more help.
https://answers.microsoft.com/en-us/msoffice/forum/msoffice_other?sort=LastReplyDate&dir=Desc&tab=All&status=all&mod=&modAge=&advFil=&postedAfter=&postedBefore=&threadType=all&isFilterExpanded=false&page=1

If my understanding is not correct, please get some screens shots to better understand the issue.

Thanks and have a nice day!

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