How to disable a plugin manually?

[n00dles101]

don't think this is a problem with the plugin system.

If you delete files you and refresh you will get an error as it reads in the original plugins.xml file.
As the file are missing you will get the above errors.

But if your refresh again the plugins.xml will rebuild itself.

Does look like its a problem with the p01-contact plugin....

I've successfully installed and deleted various plugins and I'm unable to replicate the problem.

I'll investigate some more....