Using package manager, you may encounter error messages:

Error: Encountered a section with no Package : header,

Error: Problem with MergList /var/lib/apt/lists …

Error: The package lists or status file could not be parsed or opened.

Here is a possible fix:

Open Terminal and type these commands:

sudo rm /var/lib/apt/lists/* -vf  (enter)
(enter your pwd when prompted)

sudo apt-get update (enter)

This should delete the old entries and download the latest ones, clearing the errors.

Thanks to admin at http://ihaveapc.com/2011/05/how-to-fix-problem-with-mergelist-varlibaptlists-error-in-ubuntu-11-04/ for publishing the article entitled How To Fix “Problem with MergeList /var/lib/apt/lists” Error In Ubuntu 11.04 which was published May 01, 2011. There are currently 60 comments appended to that article.