Here is a way to manually remove it.
1. Ensure that you have fully exited the application. To fully exit from Spyware Doctor please right click on the Spyware Doctor icon in the notification area (next to the clock on the Windows taskbar) and select Shutdown from the menu that appears. Please also close any instances of Internet Explorer or other browsers.
2. Perform an uninstall of Spyware Doctor from:
Start > Programs > Spyware Doctor > Uninstall Spyware Doctor
3. **IMPORTANT** Make sure that the Spyware Doctor folder (which by default would be under 'C:\Program Files') no longer exists. If the 'Spyware Doctor' folder still exists, please delete the folder.
4. Select Start>Run
5. Type in regedit and click OK
6. Please locate the following keys and remove them:
HKEY_CURRENT_USER\Software\PCTools\Spyware Doctor
HKEY_LOCAL_MACHINE\SOFTWARE\PCTools\Spyware Doctor
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\Curr entVersion\Uninstall\Spyware Doct
This will ensure that Spyware Doctor has completely uninstalled from your system and you will be able to do a fresh install for Spyware Doctor.