Help with TheGIMP program...

Help with TheGIMP program...

Okay...so I made a skin using TheGIMP. When I tried loading the .tga file to WC3 Image extractor, an error message pops up saying that the image I loaded has an unsupported compression...
Um, what does this mean and how do I fix it?

did you try to restart your computer? i know i had the same problem but once i restarted it seemed to fix what weas wrong.