synaptic error occurred during the signature verification

I didnt tick the "this affects security' option but I think maybe I should have as one of the things affected is "http://archive.ubuntu.com/ubuntu/dists/karmic-security/Release"

Thank you for taking the time to report this issue and helping to make Ubuntu better. Examining the information you have given us, this does not appear to be a bug report so we are closing it and converting it to a question in the support tracker. We appreciate the difficulties you are facing, but it would make more sense to raise problems you are having in the support tracker at https://answers.launchpad.net/ubuntu if you are uncertain if they are bugs. For help on reporting bugs, see https://help.ubuntu.com/community/ReportingBugs#When%20not%20to%20file%20a%20bug.

OK, if synaptic failing to update because something is wrong with the repositories, where exactly should I report this and if its not a bug what is it exactly???

I know its nothing wrong with my installation and this problem or problems similar to this has been ongoing ever since I updated top this new version of ubuntu.

I would classify not being able to update and a security repository not working properly as a bug.

Bottom line, this is forcing me to consider leaving ubuntu (after 3 years of being a rabid ubuntu fan) as I actually need a computer to run without bugs.

sudo apt-get update && sudo apt-get upgrade

Thanks but I wouldnt have posted this if it was that simple: I get the same
error

2009/12/15 zvacet <email address hidden>

> Your question #94110 on synaptic in ubuntu changed:
> https://answers.launchpad.net/ubuntu/+source/synaptic/+question/94110
>
> Status: Open => Answered
>
> zvacet proposed the following answer:
> sudo apt-get update && sudo apt-get upgrade
>
> --
> If this answers your question, please go to the following page to let us
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You should try adding the Medibuntu repository's keyring using the command:

sudo apt-get install medibuntu-keyring

Make sure your repository information is up to date with:

sudo apt-get update
sudo apt-get upgrade

The error about hash sum mismatch could be caused by a couple of reasons, but I usually see it when I am using WIFI. If you are not using WIFI then try:

sudo apt-get purge

Then repeat the update and upgrade as above.

sudo apt-get --yes --quiet --allow-unauthenticated install medibuntu-keyring && sudo apt-get --quiet update

Fix for me (Karmic) eventually

   > sudo apt-get update -o Acquire::http::No-Cache=true
   > sudo apt-get update
   {all good}
This was after...
  Removed Ubuntu key from Synaptic[Sourcess>Authentication], then ...

   > sudo apt-get clean
   > cd /var/lib/apt
   > sudo mv lists lists.old
   > sudo mkdir -p lists/partial
   > sudo apt-get clean

apt still had key failures so from another bug trail I got

   > gpg --keyserver keyserver.ubuntu.com --recv-keys 437D05B5 && gpg --export --armor 437D05B5 | sudo apt-key add

I'd probably skip this last one in hindsight it didn't appear to help but have included it for reference, might help someone else.

Apparently this issue has been around for quite awhile (c2006) as I dug through a few bug reports and relates to a sync failure in the repository mirrors so the rebuilding the local cache is probably the best way forward

sorry I haven't tracked bug history back properly here
Hope this helps others