, the auto-updater will not work due to a domain change. You must download and install the client manually.

Below is a breakdown of the major changes from that significant title update:

In a move that shocked competitive players, Update 21.1 slightly reduced the damage multiplier of Stopping Power when equipped with the M16A4. The burst rifle now requires two bursts to kill at long range (previously one). All other weapons (AK-47, M4 Carbine, MP5) remain unchanged.

In summary, without exact information, the best approach is to outline common features of such updates and highlight that the specific details for version 21.1 are unknown but likely involved balance fixes, bug repairs, and content improvements. I should also ask the user to verify the correct game and update version if possible.

Addressed various crashes and "checking for update" loops that had plagued players on PS4 and PC. Note for Original CoD4 Players:

: It does not fundamentally change the game's graphics but ensures it runs correctly on modern hardware. Multiplayer Longevity