While editing a file(several) in SharePoint Designer I was trying to just check in the file. Nope. I jumped through several hoops and it would not check in or let me undo checkout. I was stuck.
Seems this is something of a legacy issue. The solution is simple if not a bit annoying.
- Make a copy of the file.
- You can now check out the original file. Do so.
- Check original file back in.
- To remain tidy, delete the copy you made in step 1.
Why does that work? The new copy of the file resets the GUID apparently and releases the death grip.