How do I remove a non-responsive add-on from the UPM?

[Kim Melançon]

[Nic Brough -Adaptavist-]

I think brute force in this case.  Go to the server, find <confluence home> and look for the "plugins" directory.  Stop Confluence, find all instances of the plugin .jar or .obr and move them somewhere outside Confluence (or delete them if you're confident).  Restart Confluence.