I wanted to reinstall my OS, windows 98 SE on a Dimension L677r I booted from the CD and the setup reformatted my hard drive but when I entered the Key Code from the Certificate of Authenticity on the case I got an error that said it was invalid. I tried an upgrade version that I had for another PC just to see and got the same error. I did recently flash the BIOS, would that have any effect? In any event I can't reload the OS, what do I do now? MS refers me back to Dell as it is an OEM version

TIA