[i]Originally posted by kenorb [/i]
[B]The last time I did this all I did was to delete the 'win.com' file from the windows directory [/B]
You must have been using an OEM version of Windows 98. You need to delete the win.com file to trick a Win98 OEM to run as an upgrade. A full version non OEM does not require you to do anything other than run setup.exe.
It has been my experience, and I've completed hundreds of upgrades, that some basic preparation work tends to increase the odds of a successful upgrade. By success I mean an upgrade that does more than just complete but continues to function just as well as a clean install would have.
I have one system that I upgraded from Windows 95->Windows 98-> Win98SE->WinMe->Win2000->WinXP over several years with a significant number of hardware changes along the way. The system is my son's. We started it when he was 13 and he is now 19. He has installed nearly everything along the way from dozens of demos, to adbars, to several versions of ICQ through to MSN in several incarnations. He is still running the same setup and it runs fine. You learn how to take care of your system and it will respond appropriately. Regular maintenance goes a long way.