I have some kind of bug with patch 3.1. I installed it, I launch the game, and it says I have version 3.0. I tried reinstalling it, but it says the patch is already installed.
If the first step is not completed, see step 2.
2. Delete the game, delete all game folders and files (save files, you can hide them somewhere in a safe place), delete all entries in the registry related to the game (search for nival, heroes, etc.). Install the game, launch it, create an account (a hero profile), copy the patch to the game directory (disk:\Nival Interactive\Heroes of Might and Magic V - Tribes of the East\here, or maybe deeper - into the bin folder), install the patch.
Enjoy the game.
P.S. If nothing works, then:
1. It is possible that Windows is in such a terrible state that only reinstalling the OS will help.
2. It is possible that some program/driver/device is conflicting with the patch/game.
