I can not update my system(into jelly bean)/install any mods :(

view story

http://forum.xda-developers.com – Hello everyone. So I have unlocked/rooted my phone and it worked fine with the normal system that comes with the Andriod. But, now there is some sort of problem, I can not upgrade my phone to the Jelly Bean 4.1 (I am currently on 4.0.4 rooted version). I see a msg that states that there is an update for my phone and when I chose install now, the phone reboots and "installs" the new system But eventually it goes back into the same old system and the update did not work for some reason and I again see the install update now option. I tried a different approach by trying to inst (HowTos)