infact now i have tested for some files ...What i saw was there is an option in 
 this PI application for making these files as read only or Writeable. And what 
i saw was that when i made it readonly , i could backup the file..but when i 
made it writeable i couldnt backup the file...this explains everything...But 
still will there be a possiblity in networker to backup the file which is 
writeable...

i hope u understand wat iam sayin

+----------------------------------------------------------------------
|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