lol... to be a little bit more helpful though, lets go through a couple of senarios, with some basic advice with each one.
1. You have Kaspersky and have installed other software , which you cannot update.
if not an issue with the software itself, most likely your firewall...
try putting an exception in for the program that can't update.
as there's a good chance that it could be an issue with the software, as suggested before, try contacting vendor.
2. You just got Kaspersky and cannot update it.
Basic thing here, but make sure you're not firewalled/blocked by anything else, other security product, router firewall, etc...
This can sometimes be an incorrect date and time issue, make sure that these are set to the correct current regional time and try reinstalling...
We generally need more info here however... the more info you give to us, the more we can give to you