update manager "Encountered a section with no Package: "

[Oitrovich vasya]

ubuntu 10.10
before update in 7.03.2011

08.03.2011 update-manager:error

'E:Encountered a section with no Package: header, E:Problem with MergeList /var/lib/apt/lists/archive.ubuntu.com_ubuntu_dists_maverick-updates_main_binary-amd64_Packages, E:Списки пакетов или status-файл не могут быть открыты или прочитаны.'

[Robert Collins (lifeless)]

This is not a bug in the Launchpad software. I will open a task on the Ubuntu distribution bugtacker for you.

[RedSingularity (redsingularity)]

Thanks for reporting this. Was it an error you encountered while trying to upgrade to a newer release?

[Joshua Lückers (joshualuckers)]

We'd like to figure out what's causing this bug for you, but we haven't heard back from you in a while. Could you please provide the requested information? Thanks!

[Emilien (jeenmy1250)]

Hi. I was gettin the same error and then tried the fix that most ppl suggested and now gettin this

Get:46 http://archive.ubuntu.com natty/universe i386 Packages [7,755 kB]
Err http://archive.ubuntu.com natty/main Sources
  404 Not Found [IP: 91.189.92.161 80]

and after a few lines of i don't know what I get this

Ign http://archive.ubuntu.com natty-security/universe Translation-en
Fetched 7,776 kB in 3min 3s (42.5 kB/s)
W: Failed to fetch http://archive.ubuntu.com/ubuntu/dists/natty/main/source/Sources 404 Not Found [IP: 91.189.92.161 80]

E: Some index files failed to download. They have been ignored, or old ones used instead.

Please advise for I am new (2years) to Ubuntu