Volume Shadow Copy Fails with Error 800423F4

I am unable to backup my Xp/Pro system configuration. I have verified that
the Volume Shadow Copy service is running (thanks), have roughly 1gb of free
space on my system drive, 17gb on my user data drive, 1gb of system memory
on a dual processor Dell 420. My system is a member of a Small Business
server 4.5 domain, was converted from NT4sp6a by the XP/pro install. So some
of the 'standard' directories like 'Documents and Settings' do not exist.

Backup can be started, but fails quickly. The error reported in the logfile
is '800423F4'. I have searched every available resource and found no mention
of this error code -- presumably it is a low level status return (if this
were VMS it would be an OS message) that is just not being trapped by the
wrapper code.

The only way I am able to do backups is to disable Volume Shadow Copy in
advanced options. Obviously, if I loose my system disk, the install is toast
but at least I can recover from the usual excessive disk cleanup and
application screwups.

Does anyone have a clue as to what could be going wrong? And what I should
do to correct it?

thanks

--
Gregory Latiak
Technology Strategists, Inc.
http://www.tekstrat.com/
Tel: (416)540-7384
Images http://members.rogers.com/greglatiak/