Suddenly on my older Powerbook running High Sierra 10.13.6 App Mail stopped authenticating the MS Exchange Server. Deleting and reinstalling did not fix the problem. The message is Login Failed. I know the info is correct.
Apple Mail stopped Logging in to the Exchange Server. I deleted the account. Added it in again, but it still says Login Failed. On an iMac running 10.15.7 the same thing happened. However, on that OS I was able to let Microsoft set up the account and it finally worked. Has Microsoft made changes that no longer allow older Mac OS to Login to Exchange Servers?
MacBook Pro 13″, macOS 10.13
