Computer wants to restart every time it boots

Everytime I start my computer, whether from complete shut down or from a restart, a window pops up and tells me that my computer needs to restart to finish updating. Every. Single. Time. It doesn't make a difference if I click restart on that window, or if I just hit cancel. It doesn't tell me which program is trying to update, and my anti-virus and anti-spyware software can't find anything wrong. Please help!