Version 8 had a problem with the large disk drives.Something to do with the size of the field that and binary numbers overflowing that size I suppose.
Anyway if the Drive partition is over 2GB Family Origins 8 seems to think that it is full.It only seems to happen on Windows NT, 2000 and XP. On Windows 95 and 98 I know I have used version 8 on larger partitions than that. You can either create a partition of 2GB or less or send your backups and GEDCOMS to removable disks. A CD should work, but I suppose that a Writable DVD would again be over the 2GB limit.