The basic following steps must be followed:
1. Ensure Basic Auth is enabled in the Microsoft Office 365 Admin Center. Follow Step 1 in this article
2. Opt Out of the Basic Auth disablement
a. Opt Out of the Disablement by clicking on Help and Support in the Office 365 Admin Center
b. Submit the request to Opt Out of the disablement
c. Confirm that Basic Auth is enabled for the desired protocols. For Active Roles, choose at least SMTP and Outlook Client.
Microsoft is permanently disabling Basic Auth in December 2022, regardless of the Opt Out status.STATUS
One Identity is currently working to address this issue and provide an alternative in our 7.5.x and 7.6.x product lines. More details will be released in the coming weeks regarding the versioning and release dates. We recommend any customers presently on earlier versions to upgrade to prevent any loss of functionality.
We apologize for the inconvenience this issue may have caused and we are working quickly correct it.