ERROR PLS HELP

Hi my friends, i play Sudden Attack NA, and, i will play, without hacks, glitchs, mods, nothing illegal, but when i start, it says:

''You're using an illegal program.
The program will shut down.
You're account can be banned permanently.''

Why?
I just play in Win Vista 32 bit, and i use the green mic, is that illegal?
Thanks

Gamehi had a problem with windows vista and like every time u will get detected almost for every vista user. trying running as admin it sometimes works for me