I am guessing, based on this part of the message:
"Original Library: "HP Library NDMP DC2":
this backup was done on a NDMP (Network Data Management Protocol) device, and you are trying to restore using a non-NDMP device. This is never going to work
If something was Backed up with a NDMP device, it can only be restored using a NDMP device
You don't say what version of DP you are running, so here is the NDMP Guide for DP 7