The RUS-79U is an SMG that first appeared in COD Online as an Assault Rifle called the AKS-74U. It is one of the most Versatile SMGs in CODM, as it is very accurate and has a lot of gunsmith potential.

Clear the Cache of Your Console. Another common reason for the Call of Duty Modern Warfare Multiplayer not working error is the corrupted cache data. In this case, you can try clearing the cache files on your PC or console to fix the issue.