Automatic update fails

I have several WordPress installations for myself and friends. All of them have successfully updated to 4.0 except for one of them. I’m getting the following message…

Unpacking the update…
Could not copy file.: wordpress/wp-includes/js/tinymce/plugins/wpfullscreen/plugin.min.js

I’d rather not have to do a manual update. Is there something quick and dirty I could do perhaps delete a file by FTP or something and try again?