Why does outlook send all Emails under strange "outlook_E65A5..." adress?

Question

Hi,
I've been using outlook for desktop since quite some time now, because it allows me to switch in between different email adresses efficiently. now i have th eproblem, that most of the time outlook sends emails from any of those accounts under a cryptic sender called "outlook_e65A5..." (with a random combination of letters and numbers after the...) - which sometimes ends up in the spam fodlers of my recipients. this is incredibly annoying and after having checked every menu point in the desktop app aswell as on the website i cannot find any solution to it. already have tried to change my alias - did nothing.

Answer 1

Hi @Lorenz ,

that most of the time outlook sends emails from any of those accounts under a cryptic sender

Did this issue happen only rencently? Have you performed any special operations before it?
If you send the message directly in Web Mail, would the sender address still display "outlook_E65A5"?

According to your description, you are using the Outlook.com account, is it right? If so, based on my research, the sender would turn to the "outlook_[long series of letters and numbers]@harsh.com .com" when the alias is not a Microsoft account (such as gmail or others), for more information, please refer to this article: Outlook.com email account appears as "outlook_long series of letters and numbers@harsh.com .com" in Outlook for Windows. So it's suggested to first check your alias of account by the steps mentioned above.

already have tried to change my alias - did nothing.

According to my tests, it may need a lot time to sync the alias setting to your device, if you haven't change your alias before, please wait a few time to check if the issue has any difference.

If that's not your case, please provide me with more information about your issue, and I would continue to research with you.

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