If you manually type in the secondary connected account email address in the “From” field, the email is sent as “On behalf of” your primary Outlook.com account. If you typically use an Outlook.com account for email, this issue can occur if there are multiple aliases on the account and the 3rd party email address is the primary alias. Some customers may experience a delay when trying to create a new email address, or alias, for their Outlook.com account. This issue has been mitigated and we are continuing to monitor the issue to ensure stability. The root cause was the Fixing Office login problems deployment of an incorrect campaign data file, which led to false positive campaign detection. We have since reverted to the right data file and the outbound email flow has returned to a normal state.

Fixing them on time can help prevent the loss of important data.Ensure all IMAP/POP3 and SMTP settings are up to date as per your provider’s documentation.Rollout of the fix to all users will take few weeks, so, some users may see the fix applied by the end of September.Email clients are constantly changing, which is why it’s important to test your email every time