Don't lose sight of the basics, especially the following:
- if the hibernation file (C:\HIBER.FIL I think) is not there, is there sufficient free disk space for the system to create it? You need as much space as you have RAM, since the file is basically a RAM image.
- if the file already exists, have you tried deleting it? Note: it's a hidden file, so you may have to change settings to see it at all. Or open a command line and enter "dir C:\ /a" to show all files in C:\.