Hello,
You can run some more diagnostics on EML, but if you directly access drive 
functions such as eject & mount etc and the Drive\Library  functions are 
problematic then Legato is out of mix ( Non-Factor) and HP has to fix it's 
problems.Most library will have full diagnostics and Tape exercise 
functionality, try to get someone from HP to guide you through that.
If you rule out HP EML Hardware & continue to have problem, try using MT 
cmd & look at your zoning config ( if using FC) & firmware driver etc for 
further clues.
HTH

To sign off this list, send email to listserv AT listserv.temple DOT edu and 
type "signoff networker" in the body of the email. Please write to 
networker-request AT listserv.temple DOT edu if you have any problems with this 
list. You can access the archives at 
http://listserv.temple.edu/archives/networker.html or
via RSS at http://listserv.temple.edu/cgi-bin/wa?RSS&L=NETWORKER