k all my requirements r supported but theres 1 prob...my windows is a vista!! The game seems sick and all but the prob is that im not sure if it works 4 a vista since its saids " windows XP (only )" on the requirement part so ya... anyways hope at least 1 of u guys reply lol peace

Hey there yes it support vista cuz i got vista cuz it says that it requir XP is cuz vista wasnt there at that time (it like a year old the game

Fixes (two possible options)
OPTION A:
Right click on the desktop icon and...
then go to "properties" and then compatibility tab, and check the box that says "run this program in compatibility mode for:" and select Windows XP (service pack 2)

OPTION B:

OR.. Try reinstalling this way..
Run the install as an administrator by right clicking on the setup icon on the cd or folder it's in and then click "run as administrator" and after the install has completed....Go to the icon on the desktop and rt click it and then go to "properties" and then compatibility tab, and check the box that says "run this program in compatibility mode for:" and select Windows XP (service pack 2)

Compatibility mode is not needed at all. Make sure your drivers and DirectX are updated, and install all the Vista hotfixes.
For details see DARK MESSIAH Installation and Troubleshooting Instructions.

but on mine, ive tried it on the xp mode running thing and when i open it it says it had an engine error and cant locate buffer or something?