'Insufficient storage available' error in Backup - MarkNorri

If I try to create a 'Complete PC Backup' or 'Create backup copies of your
files and folders' in Windows Vista ( Business ), I receive an error message
...

...'Insufficient storage available to create either the shadow copy storage
file or other shadow copy data (0x8004231F)'

I have over 230GB of available space ( NTFS ) on my backup drive and a
Complete PC Backup would only require 60GB of this. Even if I try 'Creating
backup copies' and specify the backup of, for example, only 'emails' ( which
would only require perhaps 2 or 3 MB of space ), I still get the same error
message about 'insufficient space'

This is only one of many frustrating glitches I have come across with Vista
...

Any helpful suggestions welcome   ... or is it time I just 'up-graded to
Windows XP' as many people seem to be suggesting?

--
Thanks

Mark