I've not been able to complete any file backups successfully
for about two months. Some of the error messages
suggest that I need to tell my antivirus program to stop
interfering with accesses to wherever the list of previous
backups is stored - but so far I've had no success finding
out just where that is.

I have found that a program C:\Windows\System32\sdclt.exe
seems to be responsible for doing the backup, under either
32-bit Vista or 64-bit Vista, but not where it stores the data
about the backups it has finished making

Do any of you know where to find that list?

By the way, my antivirus program is Norton Internet
Security 2010, and my attempts to get Symantec/Norton
to fix this problem have accomplished little more than
getting one of their people to try to persuade me to
delete the backup program.

Also, could this backup program be revised so that
it will, if necessary, make multiple attempts to access
that list and update it, and, if necessary, will have no
problems formatting three or more DVD+RWs and
putting the backup on that many?

Robert Miles