This showed up today on my PC. While I don’t recall installing anything yesterday, two days ago I installed some sort of RAR extraction utility. I went into the installed programs and removed the utility moments ago and found this icon that matches the icon that showed up in the task bar when I got the OK2 prompt.

http://www.eficonnection.com/temp/OK2.png

Do you guys have this “Update for Zip Opener” listed in your installed programs? I don’t know how it got there.