Down Load file from this link:
after download unzip the file you get file "upgrade.lgu"
paste both of files in a clean and formatted pen drive.
insert the pendrive in your MediaNav and allow the update.
your system will be reboot after first update complete and update will be resume so please do not remove pendrive in mid of update.
after complete progress your version will be 9.1.1
if you like our service please comment on product page.and ask your friend.