Tracking cookies are not usually a big threat, and even Cnet uses them for advertsing purposes, but I too prefer to have a completely clean system. Thus, some questions and suggestions:
* Have you looked in the default directory for cookies in internet Exlorer: "local drive:\Documents and Settings\[/username\Cookies"? (You only mentioned temp files, which are held in different directories.)
* I just went to classmates.com (using Internet Explorer) and allowed the cookie to be downloaded, then scanned with AdAware and it wasn't identified as a tracking cookie. That's why it remained even after the scans. However, I did find it in the above directory, and was able to right-click->delete it.
* If you haven't done so already, download and install CCleaner (free), which scans for and deletes obsolete files, as well as cookies and temp files. That should make your job a lot easier in the future.
* I use SpywareBlaster, (free) which blocks a good portion of the nasty/unwanted ActiveX controls and cookies from ever being installed. While it doesn't detect classmates.com either, it should help you out in the long run.
* What browser do you use? If you're still using Internet Explorer, I'd suggest switching to the more secure Firefox (free). You can then customize it to automatically prompt you every time a previously unencountered cookie tries to be installed. (Go tools->options->privacy->cookies, and select "ask me every time" from the drop-down menu.)
I'm sure others will have more tips/tricks/suggestions, but those are some of the most notable.
Hope this helps,
John
OK, I've tried everything, and yet the pcpitstop privacy scan still shows I have classmates.com and partner2profit still on my machine. I have pcpitstopoptimize; AdAware; SpyBot, etc. all have been run and these two cookies are still there. I have emptied all temp files, etc.
How on earth do I find these things and get rid of them? I tried the things suggested on pcpitstop with no success. What am I missing?
Any suggestions? Since I'm a newbie just finding out about all this security stuff, sure would appreciate any help/tips/suggestions. Thanks!

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