If anyone can help with this I would greatly appreciate it. I am not being prompted to 'Allow', therefor I cannot restore it. I have tried to restore keychain access via the method suggested here I cannot contact support because keychain access is required. Mac OS Version: Version 10.13.3 (Build 17D47) I installed new Mac OS 10.13.3, did not help. I tried running the command shown here, it did not help. If you’re using an account on your Mac with other apps, such as Contacts or Messages, you can also use that account with Mail. Make sure the Mail checkbox is selected for the account. I updated my keychain password, did not help. (Your screen might look different from this one depending on the account you’re adding. In Mail, choose Mail > Add Account, select an account type, then enter your account information. I removed mail account, removed Outlook, reinstalled, this did not help. I have tried the suggestion of removing keychain files associated with Exchange, Office, Adal, as seen on different forums, and this has not helped. I am not sure which caused it, but I stopped being able to send or receive mail and since then I have been stuck in a loop entering my password twice, and being redirected to login page again. Do you want to allow this server to configure your settings?' ' Outlook was redirected to the server to get new settings for your account *** Email address is removed for privacy ***. After most recent update AND responding Allow to Autodiscover prompt :