Builds randomly failing with "unexpected logger failure"

Mattes D's Avatar

Mattes D

29 Mar, 2020 07:01 AM

We've seen an increase in the number of builds that fail randomly with:
MSBUILD : error MSB4017: The build stopped unexpectedly because of an unexpected logger failure.
System.Net.WebException: The underlying connection was closed: A connection that was expected to be kept alive was closed by the server.

It used to happen in about one in every 200 builds, now it happens in about 1 in every 15 builds. It seems to happen for both Win64 and Win32 builds, Release and Debug.

Here's links to such failed builds:
Win64 Release:
Win32 Release:
Win64 Debug:

I've found a workaround on the forums, not to use the Appveyor logger DLL, but those instructions were from 2015.

Is there anything we can do to help hunt this down?

  1. Support Staff 1 Posted by Feodor Fitsner on 30 Mar, 2020 05:04 PM

    Feodor Fitsner's Avatar

    We've performed some maintenance of our servers fleet - hope that helps. Let me know if it became better/worse.

  2. 2 Posted by Mattes D on 31 Mar, 2020 08:07 AM

    Mattes D's Avatar

    Hello. It's still happening, though it's too soon to judge the frequency yet.

  3. 3 Posted by Mattes D on 01 Apr, 2020 09:37 AM

    Mattes D's Avatar

    Unfortunately nothing much has changed, the builds still do fail rather often for the same reason.

  4. 4 Posted by Mattes D on 06 May, 2020 10:23 AM

    Mattes D's Avatar

    These failures are still occurring, any news on whether there's a fix coming?

  5. 5 Posted by Mattes D on 06 May, 2020 10:24 AM

    Mattes D's Avatar
  6. 6 Posted by Mattes D on 06 May, 2020 10:25 AM

    Mattes D's Avatar

    Also, when I click the "re-run incomplete" button, I expect only the failed jobs to be restarted, but instead all the jobs are re-queued, including the successful ones. Is that intended? Is there a way to restart only the failed job?

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