Why would he say that? But that's nothing we need to know here.
Depending on the expertise of your boyfriend, this can be difficult to find. If he installed some "Rootkit or other, then the only sure way of getting rid is to reformat the hard drive and reinstall the OS.
But there are other ways. On an unprotected wireless internet connection, someone could use Firesheep on their own computer to track the cookies on your own, and so track your movements that way. The solution there is to up your wireless security to WPA/2.
That person could, simply, be accessing your computer itself, (you don't say if he has physical access to it), and track your browser's History and Cookies. You can solve that by changing your passwords on all user accounts, including any hidden accounts, (Windows has it's own system administration account which allows you to create your own first admin capable account, then it hides itself), and also ensuring that the browser deletes all History when you exit the browser, and do not save any cookies.
However, other malware can do this, so in the first instance I would follow Grif's advice Then Please Try This.., and perform the scans suggested.
I hope that helps.
Mark
my boyfriend told me he installed a program to track all i do on my computer , emails , web sites everything, How do I find this program and how do I uninstall it, and what can I do to lock him out of going on m computer

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