This patch Call of Duty: United Offensive to 1.5c. This updates any version of Call of Duty & Call of Duty: United Offensive to the latest versions, 1.5c and 1.5.1c respectively.
This is a universal patch for Call of Duty and Call of Duty: United Offensive. Do not download it twice if you have both games.
Using Bittorrent
A bittorrent link is provided for those wishing to download the demo via bittorrent. If you're unfamiliar with bittorrent, check out this tutorial on how to use bittorrent.