hi thanx a lot for the reply...

I tried cleaning the tape drive...used brand new tapes...but it gives several 
errors while backing up..Sumtimes i get even succesful backup ..but sumtimes 
unsuccessful...so i think the main reason is that the tape drive is 
damaged..the cables are also proper for your information...

is  my findings correct?

+----------------------------------------------------------------------
|This was sent by kurianji AT gmail DOT com via Backup Central.
|Forward SPAM to abuse AT backupcentral DOT com.
+----------------------------------------------------------------------

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