Data Protector - Mutex locked

[nube999]

Greetings to all. First posting here.

I'm running Data Protector version A.06.00 with internal build version DPWIN_00373.

We run loads of backups overnight to virtual tape devices and then run a final backup to real tape, early morning.

Now when the tape backup runs, it shows a major error as below and 1 failed media agent:

[Major] From BMA@lgldp01.lob.customername.com "HP:Ultrium 3-SCSI_6_ajax" Time : ........
[90:63] By: UMA@servername.lob.customername.com@scsi2:0:3:0
Cannot load exchanger medium (Mutex already locked.
System error: [122] The data area passed to a system call is too small)

Does anyone know what this is all about and what the resolution is?

Thanks in advance.