I got a big problem in backup

My config
1. HP DL380G2 with 2GB memory
2. Netware 6.5 SP5 - CPR release
3. BAB 11.5 SP1, with patch Q078480 and Q079611
4. TSAFS version - 6.51.04

I am now doing full backup on the system (with several local disks). The
condition is the backup will stop at the session. The task will not jump
to next session when I press Del at netware BAB console. Error E0007
appears ar BAB message. Meanwhile, the CPU utilization is keeping low,
the system is not freezed. What I only can do is run astop and reboot. I
also added this in asconfig.ini

[NetWare Backup/Restore]
UseMultipleReadThreads = FALSE
performanceNonNakoma = TRUE

Anything I can do for it?