Data Protector Express Hangs on Creating Snapshot

[SIMITS]

The short of the problem:
While running a daily incremental backup, the host state never finishes creating snapshot and does not complete the back up.

The long of the problem:
Specs:
The OS in Windows Server 2003 R2 Service Pack 2
Data Protector Express V3.50sp2(build 34497)
HP Storage Works DAT 160 USB External Tape Drive

Issue:
As outlined above, the daily backup job never completes. It has been running for well over 10 hours and normally completes in less than 2 hours.

The rotation that I am using is as follows:
Daily: incremental overwrite 6 sets
Weekly: Differential overwrite 6 sets
Monthly: Full overwrite 6 sets
Yearly: Full overwrite 2 sets

Current logs show:
Daily sets 1-3 completed,
Weekly set 2 completed,
Daily Set 4 completed.

The following daily set failed to complete and was manually terminated. The following daily sets failed to complete and also needed to be manually terminated.

Additionally, if I try to run the next scheduled set (which should have been daily set 5) Data Protector Express lists the media as daily set 4. Even manually setting the next daily set to a different rotation, Data Protector still lists the media set as daily set 4.

So in summary, the successful backup was daily incremental set 4. The next rotation should have been daily incremental set 5; however data express reverted to daily incremental set 4, and has hung up on creating snapshot phase of the backup process.

Has anyone had similar problems?

Thanks in advance.