The package system is broken

Updating the software using Ubuntu’s software updater and got the following message:

The package system is broken: Check if you are using third party repositories. If so disable them, since they are a common source of problems. Furthermore run the following command in a Terminal: apt-get install …

[FIXED] Tensorbook: How to turn on keyboard backlights?

Could anyone tell me the keyboard shortcut to enable keyboard LED backlights?