I am continuing to have failed backups.
First I had a problem with my external drive not being tightly connected. Fixing that seemed to solve the problem for a while.
Then I discovered by accident that that the problem I was now having with doing validation, occurred only when Zone Alarm Extreme Security was running. When I closed Zone Alarm, I was able to do the validation of my backup.
After installing a new version of Zone Alarm Extreme Security, and the latest build of TIH 6868, I was able to get one good backup, but only after I turned ZA off completely.
Now I am not able to get any good backups at all, even if ZA is totally off.
The only error message I am getting is a generic "Error occurred while writing the file. Click Browse to specify another location, Retry to try again, or click Cancel"