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Good afternoon,
I have a a Mac computer (version 10.13.10).
I use MS Entourage for my emails. (Version 12.0.0 ( 071130) Microsoft Entourage 2008 for Mac)
I don't have a problem receiving emails, however, when I try to send an email, I get this error message:
Error: "Request failed. Mailbox unavailable."
Explanation: mail could not be sent.
Account name: Fred Jardine
Error - 17099
I was able to send and receive emails for many years until November 23, 2017. Since that date, I can receive incoming emails, but I am no longer able to send outgoing emails (they are stuck in my outbox).
Please advise.
Fred Jardine.
Processes in Microsoft 365 for setting up Office apps, redeeming product keys, and activating licenses.
Locked Question. This question was migrated from the Microsoft Support Community. You can vote on whether it's helpful, but you can't add comments or replies or follow the question.
Answer accepted by question author
It sounds like your email host has made a change to their server that requires you to change your settings in Entourage. Go check the provider's support pages and see if there's some new setting you need to use.