Try using this free tool from microsoft, it's called windows clean up utility and may work for you.
Download from here: http://support.microsoft.com/kb/290301
Then save to your desktop > install it > run
Then see if it finds ad-aware (7.0.2.x) if it does click remove.
I'm also having similar issues for Ad-Aware 2007. When I try to use it, I receive the error message:
"System error: 1810 has occurred. Description: Service is not online. Application Terminates."
I then decided to simply upgrade to 2008, so went to uninstall 2007. Here's the error message I received when I tried to do that:
"Error 1720: There is a problem with the Windows Installer package. A script required for this install to complete could not be run. Contact your support personnel or package vendor."
I went to the link you provided above, but it only pertains to Microsoft Office products (Word, Excel, Access, PowerPoint, etc.), Outlook, FrontPage, Publisher, and Project. It mentions nothing about 3rd party software. I'm uncomfortable installing this clean up utility if I don't need to. I do have RegistryFix and have run it in an attempt to fix the issue, but was not successful.
So...now I'm here. Basically, I just want to uninstall 2007 so I can upgrade to 2008. Help!!
Thank you for your time,