If you're having problems installing or removing AVG, try the AVG Removal Tool
This comes straight from Grisoft:
- If you are using AVG Free, you must uninstall it first as follows: Start->Settings->Control Panel->Add/remove programs->AVG Free->Uninstall.
- If AVG Trial Edition is installed on your computer, it is not necessary to uninstall it before installing the full version. You can simply activate your AVG with your new Sales/License Number as follows: AVG Control Center -> License component -> Re-Activate-> copy & paste or enter your new Sales/License Number into the last textbox and confirm by clicking on the Activate button.
- If AVG Anti-Virus Professional Edition (Trial) is installed and you purchased AVG Anti-Malware, please do the following:
- download the latest AVG Anti-Malware installation file
- run this file and choose the first option - ADD/REMOVE COMPONENTS
- enter your AVG Anti-Malware License Number into the installation form
- select the AVG Anti-Spyware component from the list of components to install
- finish the process and restart your computer
- (For AVG Anti-Virus Plus Firewall Only) If you are using one of the older versions of AVG Anti-Virus plus Firewall, we recommend you to do a "Repair installation" by launching the latest downloaded installation file and choosing the "Repair installation" option. Finish the repair process and reboot your computer.