We installed Kaspersky for Linux Mail Server on one of our web servers.

This was a big mistake - the installation was ok, the updater ran ok, setup.pl ran ok but now the server is not sending or receiving any email.

The uninstall script does not run - what should we do?

Why didn't you install kav4ms on a *mail server*, instead of one of your web servers?

Seriously, provide the name of the mailer system that you run on the server, exact name and version of the KL application and more details on the problem - can you mailer accept connections on port 25, what do you see in the logs while sending a message to it, what do you see in the mailer's queue, etc...