Maybe you could maybe try rebooting while hitting the F8 key to get to alternate boot modes. One of the modes is a step by step boot. If you find the name of the missing file, you could reboot again to safe mode or DOS prompt (using F8 again) and replace the missing file using your Windows install CD.

forgot to add, if that does'nt work - boot to dos using a floppy disk and retrieve the missing file from CD as in the prev post. You may have to work with CAB files from the CD and the extract utility but the missing file should be in there somewhere.