Brian, We had a rogue 3590 drive (1 of 4 in 3494) like this - failing
repeatedly over a long period with load/unload problems. We had quite
a few components replaced but the cure was to update the microcode to
D016 27A - and we have had no problems since August. I believe there
is later microcode available now too.  Hope this helps.

We have found the 3494 to be extremely reliable and the 3590s pretty
good. But, we have had more tapes fail than we would have liked - with
errors including: unrecovered read/write errors, lost VCRs, lost tape
leader, inability to label tapes ... about 20 in all out of about 700
tapes in active use. Some tapes have been sent for analysis in Tucson
but we have not had the results yet.

Improvements in the drive microcode since we first installed the decks
(September 1995) has helped with some problems - the load/unload faults
and the problems with tape labelling.

Regards, Sheelagh

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Sheelagh Treweek                         Email: sheelagh.treweek AT oucs.ox.ac 
DOT uk
Sheelagh Treweek                         Email: sheelagh.treweek AT oucs.ox.ac 
DOT uk
Oxford University Computing Services     Tel:   +44 (0)1865 273205
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