Hello,

I wish to update a debian 4.0 server we have but cannot get past the following error message.

my keys are as follows:
Any help would be good.

try the following

apt-get install debian-archive-keyring

I just gave that a try but unfortunately it did not work.

Can you check This will tell you (a) if it's already installed (the line will begin with an "i" and (b) whether the package is in your repos. You may be missing something from your sources.list file.
cheers,
jdk

Here is the results of the command:

aptitude search debian-archive-keyring
i debian-archive-keyring - GnuPG archive keys of the Debian archive

Ok that means you already have debian-archive-keyring installed that's why your apt-get command wouldn't install it - it was already installed.

The messages you received originally were not errors; they were warnings. Messages beginning with "W:" are warnings; those with "E:" are errors. Your update completed successfully. apt-get was just telling you that you need to update your keyring with more recent public keys from the repos on your sources.list file. Install the gui-apt-key package if you want an easy way to update your keys. As you can tell from the date, this is the key that needs updating.
cheers,
jdk