Very few users run into problems with deleting Magento extensions. All you need is to follow the Easy-to-Use guide:
Step 1: The module should be disabled in this file:
/app/etc/modules/<your_module>.xml;
<active>true</active> is to be changed for <active>false</active>;
Step 2: In case there is any dependent MySQL table, remove them;
Step 3: Then remove the config record for the module you want to delete from the core_recourse table in the database;
Step 4: Cut out the <project_root>/var/cache folder;
Step 5: Refresh the home page of the website. The extension has been successfully removed now!