ok so i downloaded a file (a setup file) and i accidentally clicked on it without checking what it was, as it turns out it was from a site called addsite. now everytime i go to a web page on any browser, it pops up with a stupid amount of adds. this spyware has really slowed my computer down and is really annoying, i was wondering if anyone knew how to get rid of it.  i have already tried uninstalling it but it didnt work. please help me!!!...

Tried running a spyware removal program or a virus scanner?
And telling us the setup file may be useful

yes i ran ad aware twice (once a couple of days ago and once today) it came up in the scan and i deleted it, but it keeps coming back, the setup name was just setup

Have you checked add/remove pograms for this? When you did the ad/spyware scan / uninstalled it did you have your browser running (remember what's in use can't be deleted)? You can also run these scans (and a virus scan) in safemode if doing it in normal mode has no result.

ive done all that, except the safe mode one, how do i enter safe mode from bootup?

Continuously click F8 on start up, a menu will presented where you can choose safemode.

If I may ask what Spyware/Antivirus protection have you got on your computer?

i got McAfee Virus Scan Enterprise 7.1.0 and Ad-Aware with latest definition files