rc=1837 means you have all objects excluded from backup.
In looking at your DSM.OPT file, you have:

   EXCLUDE                   "*\...\*"

This is the problem.

You don't want to EXCLUDE items in the DSM.OPT file
for Data Protection for Exchange... and if you do.. you need to follow
the example in the DSM.SMP file.  The objects have special naming.
Remove the EXCLUDE statements and the backups should work.

Thanks,

Del