I'm running version "12.04 LTS" on the machine with the problem.

  The message pops up while Update Manager is initializing, and it looks
to me like an issue with the database of installed packages, not the
list of updat sources.  Although I don't suppose I can be absolutely
certain that isn't corrupted TOO...

  Here's the message text:
----------------------------------
An unresolvable problem occurred while initializing the package
information.

Please report this bug against the 'update-manager' package and include
the following error message:

'Encountered a section with no Package: header, 
Problem with MergeList
/var/lib/apt/lists/us.archive.ubuntu.com_ubuntu_dists_precise-updates_universe_i18n_Translation-en,

The package lists or status file could not be parsed or opened.'
----------------------------------




-------- Original Message --------
Subject: Re: [PCBUILD] Ubuntu and Thunderbird
From: Derek Buchanan <[log in to unmask]>
Date: Mon, July 01, 2013 8:51 am
To: [log in to unmask]

David,
 I am not going to be much help with the Thunderbird question, but
here is my best guess for Ubuntu updates since you don't list what
version of Ubuntu you have. Is it possible that you can pick another
download source? Your connection to the respositories might have to
be reset. Try the following..

From Update Manager, click on Settings, click on the Ubuntu Software
tab, and select another mirror under "Download From"[select main
server]

hope that helps,
Derek

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