I have an issue with the 0xArt Speed Optimizer plugin where it's giving an error when trying to view messages on my site. The odd thing is that this plugin is deactivated on my site. I don't actually use it and today I decided to try to uninstall it since it always causes me issues when I do activate it.

The weirdest thing is that it won't uninstall from the admin panel. If I try to "uninstall" it just goes to a blank white page. If I then go back to my plugins list it's magically been activated! The exact opposite of my goal.

I have a mail into the developer about the error that conflicts with messages as well as uninstallation issues but looking at the plugin forum I suspect it will also go unanswered.

At this point now, my question that maybe someone else can answer is...how do I remove this plugin if I can't do it through admin panel?
I assume I would FTP into the server but I'm not sure what steps I would take to make sure the plugin is removed fully and won't cause errors later.