"In honor of our fathers" - "One Khan, One Clan" [Campaign 3, Mission 2]

Hey guys, I have a problem: I've completed the entire "Wisdom of the Earth" map, but at the very end, as soon as I approach my hero, the game freezes. Nothing responds to clicks, and when I press Ctrl+Alt+Delete, it says the game is running, but when I try to end the task, it says the program is not responding. What should I do? The disc is not a pirated copy; it's completely clean, and I've been struggling with this for over six months.