I have to recall my last message. I did some extra issues on the bug and opened a new bug:
https://github.com/BOINC/boinc/issues/5975
For now, removing the folder virtualbox in projects allow you to start without reinstalling again. You have to do it every time. Compared to my Windows computer, this folder should not be there.

For now, removing the folder virtualbox in projects allow you to start without reinstalling again. You have to do it every time. Compared to my Windows computer, this folder should not be there.

Presumably this only happens with projects that require VB. Does it only happen with one project? If so, could it be the Mac app from the project not clearing up after itself rather than a BOINC issue?

That said, in an ideal world the BOINC code should be resilient enough to cope with that.

Whatever the cause though, I think your latest discovery should go a long way in tracking down the source of the problem.

I was able to fix this without a reinstall. The directory /Library/Application Support/BOINC Data/projects/virtualbox has a different owner (boinc_project instead of boinc_master like all the other directories), but it is also missing READ permission for Others. The last is the one that seemed to fix it for me. I executed the following commands and I was able to stop/restart the software with no issues instead of having to reinstall every time.

cd "/Library/Application Support/BOINC Data/projects"
sudo chown -R boinc_master virtualbox
chmod -R o+r virtualbox

Ocne I did both of those, I've had no more issues. Let me know if it works for you, but it would be nice if they fixed it in the install.

Ocne I did both of those, I've had no more issues. Let me know if it works for you, but it would be nice if they fixed it in the install.

This issue should be fixed in the next MAJOR release
Client/Manager 8.2.0, Due by March 30, 2025
See https://github.com/BOINC/boinc/issues/5975