Cannot Update Ubuntu

Recently, When I was trying to update ubuntu, I was getting following error message:

E: Could not get lock /var/lib/apt/lists/lock - open (11 Resource temporarily unavailable)

E: Unable to lock the list directory

After searching on Ubuntu forums I found the solution to solve this Problem.

Use following command to see is their any synaptic pkg manager running?

      $ ps -e | grep apt

If yes, then kill all those processes using 

  $ sudo kill -9 processID

Then remove lock file from ur system:

  $  sudo rm /var/lib/apt/lists/lock

Now try to update ur system. It should work. Atleast it worked for me.