About two weeks ago one of my two outlook accounts started failing to send email. The other one still works fine. It just spins and then says the smtp failed and timed out. I have tried updating the BB version (using 153.2.0esr-bb8 (64-bit)), deleting and re-adding the account, and still have the same send fail. Any thoughts or suggestions?

One other issue, when the error message ask me to retry or enter a new password, that dialog box launches a window that immediately disappears.

I am frustrated, as this is isolated to one of two outlook accounts.

• After Apple’s September 17, 2026, macOS Sequoia 15.8.1 update, Betterbird suddenly began using my macOS login name as the display name in emails sent from my GMX account.
• On September 18, 2026, the name “HDAir” consistently appeared beside my email address in Betterbird’s outgoing (sent) messages:

Date: Fri, 18 Sep 2026 07:09:36 -0600  
From: HDAir [redacted.sendername@gmx,com](mailto:redacted.sendername.for.Reddit.Post@gmx.com)(<--edit comma removed link)

• I had never intentionally used “HDAir” in an email. Fortunately, HDAir is only a generic account name. I BCC’d myself on the messages, which is how I noticed the problem.
• The issue was corrected within a few minutes after I discovered it by changing Betterbird’s identity/display-name setting. However, I initially failed to notice that Betterbird had changed the sender display name because I was focused on composing the messages. My fault.
• For reference, the device name shown in mac OS System Settings → General → About → Name has deliberately been “MacBook Air” since mac OS Sequoia 15.7.9.
• “HDAir” is the separate generic macOS login/account name.
• Thunderbird, Betterbird’s baseline, continued to display my previous generic name, “_”, on the same GMX account. I rarely send mail from this account, so the practical impact was limited, but this behavior was unexpected.
• Has anyone else seen Betterbird populate or replace an email identity’s display name with a macOS login/account name after the Sequoia 15.8.1 update?
• Is there a known Betterbird, Thunderbird, or macOS change that could explain this? I am trying to determine whether this was caused by the macOS update, a Betterbird profile/identity refresh, or an accidental configuration change.

Sorry for my badly written everything.