Can't simulate using Win7 in my hp pavillion dm1, what's the problem?

I have installing and uninstalling PSPICE over and over again because of this problem. The dialog box said that it had conflicts with .sch extensions and wil not operate. i looked up what that .sch was and found out that it was only the task scheduler, a default program of win7. i asked my other classmate using win7, and he told me that his was working. is there any problem with PSPICE or is it my hp pavillion dm1 netbook that has a problem? I would appreciate your help..really! thanks