ok uys, this ones a doozy, i've googled it, no luck. SOS (switch on schoolhouse) is an app from Alpha Omega Academy. yeah, i'm trying to use it, but i can't get it to install on this computer. It says i have all the necessary software, but this is the message i get: "Fatal error during installation. Error code: 0x00000643" I've tried up and down the ying-yang, and i haven't a clue left as what to do, any help, would REALLY be APPRECIATED...untill then i'll just keep trying, thanks people.