Found a swap file by the name

Accepted answer fails to mention how to delete the .swp file.

Hit "D" when the prompt comes up and it will remove it.

In my case, after I hit D it left the latest saved version intact and deleted the .swp which got created because I exited VIM incorrectly

.MERGE_MSG.swp is open in your git, you just need to delete this .swp file. In my case I used following command and it worked fine.

rm .MERGE_MSG.swp

Looks like you have an open git commit or git merge going on, and an editor is still open editing the commit message.

Two choices:

1. Find the session and finish it (preferable).
2. Delete the .swp file (if you're sure the other git session has gone away).

Clarification from comments:

• The session is the editing session.
• You can see what .swp is being used by entering the command :sw within the editing session, but generally it's a hidden file in the same directory as the file you are using, with a .swp file suffix (i.e. ~/myfile.txt would be ~/.myfile.txt.swp).