I have a HP Pavilion 7850 with XP OS. The computer originally came with Me OS, after few months I goy fed up with it and changed to XP OS. During this period I have never updates the BIOS. Recently in an attempt to increase the RAM from 128 MB to 512 MB, I was stuck with the fact that my current BIOS does not allow 512 MB RAM. I went to HP website and downloaded the most recent (and the only one available) BIOS update for Pavilion 7850 with XP OS. The problem I am facing that I get error message upon installation of the BIOS " file has no update number", I tried it several times but kept getting the same message. What could has gone wrong, any guess? Thank you all.