Installation keeps failing.

[Sershonius]

I keep getting this error 50% through the installation. (Using the newest nightly version.)

Error during installation process (com.msys2.root): Execution failed (Unexpected exit code: 1): "C:/msys64\usr\bin\bash.exe --login -c exit"

This isn't an issue with antivirus or anything as I've already tried disabling those and doing it. I've tried restarting constantly and trying again but it still gives me the same error. None of the fixes I've seen online have worked.

[Olimon7661]

Same problem.

[DspHack]

I have the same problem. I tried running the offending bash.exe in PS and got the following error:

C:/msys64\usr\bin\bash.exe
      0 [main] bash 1922 dofork: child -1 - forked process 25676 died unexpectedly, retry 0, exit code 0xC0000142, errno 11
bash: fork: retry: Resource temporarily unavailable
1073982 [main] bash 1922 dofork: child -1 - forked process 13424 died unexpectedly, retry 0, exit code 0xC0000142, errno 11
bash: fork: retry: Resource temporarily unavailable
3144100 [main] bash 1922 dofork: child -1 - forked process 21468 died unexpectedly, retry 0, exit code 0xC0000142, errno 11
bash: fork: retry: Resource temporarily unavailable
7210753 [main] bash 1922 dofork: child -1 - forked process 35112 died unexpectedly, retry 0, exit code 0xC0000142, errno 11
bash: fork: retry: Resource temporarily unavailable

[baburton]

FWIW, I get this error also on a fresh install of windows 11 (which is running inside a qemu virtual machine).

The 2025-02-21 msys2 installer works fine on a fresh windows 11 install. The 2025-06-22 and 2025-08-30 msys2 installers do not. So the breakage must involve something that changed between those releases.

Attempting to work around this by installing 2025-02-21 and then upgrading via pacman fails also (and appears to have the same root cause). When running pacman -Syu, after the core system upgrade, it asks you to close the terminal to terminate all msys2 processes - from here on you cannot open a fresh msys2 terminal again. (Opening any of the msys2 terminals from the start menu will flash up a blank mintty console which then closes immediately with no output.)

[baburton]

A further update: installing 2025-02-21 and upgrading everything except msys2-runtime does work. So it would appear to be something that changed in msys2-runtime since version 3.5.7-2 that is causing the problem.