Hi Dan, in the end I had to use a different office 365 account. I appreciate that isn’t very helpful. MS support said the account was corrupted, and having my local org recreate the account should solve it. But it didn’t, but perhaps that could work for you, if it’s an option. Eoin
No problem and I appreciate the reply - I was thinking maybe next port of call would be to see if I could have my guest access revoked and then reinstated (as I could access it at one point) and see from there.