Well it certainly isn't a faulty drive.. ;-)  

Check that CDI has been disabled for the Virtual Drives 
verify the EDL hasn't surpassed its licenced capacity
ensure Tapes themselves haven't been created with "capacity on demand"
Ensure the Storage node using the drives has no issues itself using the
devices, which would cause networker to assume drive issue and disabling
them.

-----Original Message-----
From: EMC NetWorker discussion [mailto:NETWORKER AT LISTSERV.TEMPLE DOT EDU] On
Behalf Of Otto Vestmann
Sent: Tuesday, 7 April 2009 6:53 AM
To: NETWORKER AT LISTSERV.TEMPLE DOT EDU
Subject: [Networker] Virtual tape drives give error and go to servmode

Hi I have this problem that two virtual tape drives switch to servmode
and 
in the volume message window I get this error read open error: Access is

denied. This happens with two drives and after putting them to enable
they 
switch themselves again.
We are running EDL with 7.4.4 Networker.
Does anyone know this and how to deal with it?
Best regards Otto

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