I just had two tasks error out
https://milkyway.cs.rpi.edu/milkyway/result.php?resultid=998035852
https://milkyway.cs.rpi.edu/milkyway/result.php?resultid=998036013
That error 194, if it follows standard Windows error codes, supposedly means "iterated data exceeds 64k", and I had one more like that some days ago on Asteroids@home.
This is a new computer and I do have some concerns about it, so any idea what that's about? It seems to indicate a problem with the instructions, not with the processing, but I can't find specifics about it and I never saw anything of the sort on the old one, on any project that I ran on it.

Hmm... EXIT_ABORTED_BY_CLIENT and than "The operating system cannot run" in the std_err. What Antivirus are you using? Any McAffe crap or similar perhaps? Exclude BOINC data dir from scanning anyway and see if it comes back.

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None bar the one included in Win 10 at the moment, didn't switch the AV license from the old computer yet.

Found an old thread on SETI@home talking about it, https://setiathome.berkeley.edu/forum_thread.php?id=73704
What I found most relevant after a quick skim of the first page, quoted from another thread, is "One of the last things an app does before exiting is write an empty "finish file", and that error indicates the app didn't exit within ten seconds after writing that file. I think the error was likely caused by shutting BOINC down after the file was written but before the app had gotten to its usual exit" In my case it wasn't quitting or crashing BOINC, but likely the task getting suspended at such an... inopportune time when I unsuspended Asteroids@home to allow some remaining tasks to complete (since I want to switch back fully to MW@h now that I can run it again) and it switched straight to those since the deadline is approaching.
That is assuming that the issue wasn't fixed in the 11 years since those posts...

And that "The operating system cannot run ..." is the argument for system error 194 I see, https://learn.microsoft.com/en-us/windows/win32/debug/system-error-codes--0-499-

None bar the one included in Win 10 at the moment, didn't switch the AV license from the old computer yet.

I'd recommend to keep it that way and exclude BOINC data dir from scanning to aviod any unnecessary issues in the future.
Anyway, than the issue shouldn't come back. When resuming tasks of another project, I usually do that one after one, not all at once, to see what BOINC does, at least until I see one or two tasks remaining in "ready to start" state. This might also help in situations like yours.

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