Failed to get datat for "copy mode"

I am new, so please be patient & feel free to suggest.

my os is winxpro
I am running comodo back-up
I am backing up to a CD

I had set up & run three back up jobs. In the process of setting the fourth back-up, the program locked-up.
When I restarted the program I got the following errors:

Failed to get data for “copy mode”
The procedure entry point IsThreadDesktopComposited could not be located in the dynamic link library USER32.dll

Also only one of the jobs is listed.

I uninstalled, re-downloaded, re-installed.
The same errors exist.

Any suggestions?

Thank you