laptop display problem

i have a toshiba Satellite M115-S3094 i have had it about 13 months, about 5 months ago the colors went whacko on it. the green start tab is green, and all the black is white, pretty much all the colors are messed up…. i have been trying to fix it forever…. and i cant seem to figure it out. The laptop was not damaged at all… went to use it one day and it turned on like this… everything else on the laptop works great… if you hook it up to an external monitor it also works fine. Any chance its not something internal with the screen? there are no flickers, spots or any such thing on the screen the colors are just like backwards… i wiped the laptop with the disk from toshiba and the problems persisted. any ideas?

Hello tomps27 and welcome to WTT, You've done some great troubleshooting work. It sounds like it is a problem with the laptop screen, since it works fine with the external monitor. If it's still under warranty, I'd take it to the manufacturer. Otherwise, Google knows the best prices :). Regards, Ax