> Hi Michael,
> 
> I have seen this or a related problem on different sites using (always) 
new 
> (2011-2012) overland tape libraries.

This library is from 2008 ...

> The workaround was to label the (blank) tapes on a different server. 
Does it 
> happen with labelled tapes or only blank ones?

Labeled tapes. (altho I have seen it happen once, maybe twice, when 
labeling blank tapes). And I don't have another server to use, nor another 
LTO-4 drive to label tapes.

> If you cannot downgrade,  that may happen because the 1.0.6.3 
> driver files are 
> still on the windows directories. Try uninstalling the 1.0.6.3 
> driver, remove 
> all the 1.0.6.3 files  and reboot the windows machine. That might work.

I don't know what all the 1.0.6.3 files are. :-) I did reboot between 
uninstalling, and trying to re-install, to no luck. I will try again 
today, if I can.