This issue is temporary and should be automatically resolved by the server. If not, please contact your mail provider.
@beamer138 Hopefully Microsoft will give you are reply back soon as to what the issue is.
As @Gary says in this previous EMC Thread on this issue, the only way to know would be if you are a eg: eM Client Pro customer and lodged a support ticket, eM Cient Support can then investigate your EWS logs and confirm where the issue is. If you like using eM Client, i would suggest to do that.
Gary
Jun 9
It is unlikely that the problem can be resolved in eM Client because the error says it is a server issue.
But, if you have a Pro License, with a current VIP Support subscription, you can open a ticket directly with us. We can investigate your EWS logs and confirm where the issue is. But if it is a server issue, you will need to take that up with the mail provider as the error says.