You always need to unistall all the hacks before unistalling the module. If hac is not removed, the system will keep trying to call the module no matter is was removed.

To manually remove the hacks:

The hack modifies the following files:

/default.aspx.vb

/admin/skins/nav.ascx

/admin/skins/solpartmenu.ascx

and before modifying each file, it creates a backup file named: filename.dsbackup.currentdate.resources in the same folder as the file

Restore those files and all the hacks are removed.