Duplicate of:

No Battery Status Icon

I have just recently upgraded from 11.04 "Natty Narwhal" to 11.10 "Oneiric Ocelot" on my laptop, but do not have any battery indicator (which should be located between the volume and date indicator in Unity).

I have already run

sudo apt-get install indicator-power

and got the following output:

Reading package lists... Done
Building dependency tree       
Reading state information... Done
indicator-power is already the newest version.
indicator-power set to manually installed.
The following packages were automatically installed and are no longer required:
  //list of packages
Use 'apt-get autoremove' to remove them.
0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded.

In addition, I have already tried reinstalling, but still don't have a battery indicator. What else can I do?