Desperately need some help

Question/Problem: An annoying message keeps popping up. It says:

The application or DLL C:\WINDOWS\system32\msansspc.dll is not a valid Windows image. Please check this against your installation diskette.

It appears when I start my computer up and when I try to access certain programs.

Operating System, Version and Service Pack: Windows XP

Your level of experience: Beginner. I know nothing about computers.

I tried running a virus scan, but it didn't detect anything. I also tried Ad-Aware, but it didn't solve the problem.

What's the best way to get rid of this?

Edit: No longer need help.