Was this this something you tried to installed yourself? Are you sure you want and need this?
It seems like something is triggering the installation of "Winampa.exe" or some component of it. Like if the installation was not yet completed.
If you want to "undo" that, I guess you should check in your "Add / Remove Programs" list and select the specific program (winamp maybe ? ) so to uninstall it. Then reboot and test if the same behaviour still is repeated.
The best option would be to open a new topic in the "Viruses and Worms" subforum. I am NOT saying this is for sure some malware, so please don't panic. What I man is that people that usually help in that subforum probably are more capable of identifying the problem and they may request from you to run something so to give them some resulting log. With that specific info, they might be able to give you more specific instructions. You can post there a link to this same topic too.
Of, course you can try by yourself the list in "Add / Remove Programs", remove "Winamp" (or whichever the program is) if it is there and reboot.
In any case, please report back.