error: cannot open .git/FETCH_HEAD: Invalid argument

Question

I'm using Git (from the GitHub for Windows distro) and trying to pull from my repo and I get the following error:

D:\Code\dopey-weaver [master]> git fetch
error: cannot open .git/FETCH_HEAD: Invalid argument

D:\Code\dopey-weaver [master]> git fetch --verbose
error: cannot open .git/FETCH_HEAD: Invalid argument

This isn't the "Permission denied" of many other questions, so it seems like I'm a special snowflake... I can open .git/FETCH_HEAD and it looks fine(?):

010779f14f5bdf1d2d806a0ce0ac4c5e50314186        branch 'master' of https://github.com/nicktimko/dopey-weaver

I think I have some conflict with what's on the remote so I should be pulling/merging, but I can't even fetch to start... The error message on push does look a little long (is this the equivalent of hg saying "this would create multiple heads" in not so many words?)

D:\Code\dopey-weaver [master]> git push
To https://github.com/nicktimko/dopey-weaver.git
 ! [rejected]        master -> master (fetch first)
error: failed to push some refs to 'https://github.com/nicktimko/dopey-weaver.git'
hint: Updates were rejected because the remote contains work that you do
hint: not have locally. This is usually caused by another repository pushing
hint: to the same ref. You may want to first integrate the remote changes
hint: (e.g., 'git pull ...') before pushing again.
hint: See the 'Note about fast-forwards' in 'git push --help' for details.

Answer 1

The problem appeared to be because the volume (an exFAT drive) was dirty, thus read-only, and needed to be run through chkdsk. So, to solve:

1. Launch PowerShell/CMD in elevated mode (easy way being to right-click on the short-cut in the Start menu and pick "Run as administrator")
2. Run chkdsk on the desired volume, e.g. chkdsk D: /X (/X forces a dismount)
   • If you're having this problem on the primary partition (C:), you'll probably have to do chkdsk at startup...somehow.