My nephew sent me a text message recently telling me he could happily play Call of Duty: Modern Warfare 3 Single Player Campaign and Spec Ops without any problems. Whenever he attempted to play the Multiplayer MW3 game it did not work. The error said something in the

neighborhood of, “Steam Error Cannot Play Modern Warfare 3 Multiplayer, Please Tray Again Later”. I have been able to play Call of Duty: Modern Warfare 3 multiplayer without any problems on my computer. So this problem puzzled me a bit. I did some research and tried a few things to fix the problem. While researching the problem I also found a similar Modern Warfare 3 error that is happening to people, “iw5mp.exe has stopped working.” There were various suggestions and fixes people suggested. Below are the ones that fixed my nephews problem and allowed him to play Call of Duty: Modern Warfare 3 once more.

Please try Solution 1 first. If that does not work then proceed to solution 2.

Solution 1
1.1 - Open up Steam (Do not open up Modern Warfare 3. If it is open please fully close/exit the game).
1.2 - With Steam open RIGHT-click the Steam icon on your taskbar which is usually located on the bottom-right of your screen.
1.3 - Select “Library”
1.4 - RIGHT-click, “Call of Duty: Modern Warfare 3” and select “Properties”
1.5 - Click the “LOCAL FILES” tab
1.6 - Click the “VERIFY INTEGRITY OF GAME CACHE” button
1.7 - Please be very patient. This process may take up to 20 minutes.
1.8 - Once that is complete within the exact Library section you were just in go through the process again but for “Call of Duty: Modern Warfare 3 - Multiplayer” (Do the “VERIFY INTEGRITY OF GAME CACHE” thing for this too).
1.9 – When you have verified the integrity for both “Call of Duty: Modern Warfare 3” and “Call of Duty: Modern Warfare 3 – Multiplayer”, RESTART your PC

Play Call of Duty: Modern Warfare 3 Multiplayer. Does it work? If yes then have fun :-)
If it still does not work try Solution 2.

Solution 2
2.1 – Open up Modern Warfare 3
2.2 – Select the Multiplayer menu (do not hit play)
2.3 – Go to OPTIONS then select “Voice”
2.3 – Select “Yes” for “Mute All”
2.4 – Exit the game and restart your PC
2.5 – Open up Modern Warfare 3 multiplayer (but do not play it yet)
2.6 – Go into the Options>Voice again and make sure that “Yes” is still selected for “Mute All”
2.7 – If everything is okay then play Modern Warfare 3 Multiplayer

Do you have a different Call of Duty: Modern Warfare 3 multiplayer error message? Or maybe you have some other COD: MW3 multiplayer problem? If so feel free to post your exact problem below. As much detail about your problem including specific error messages you are receiving would be great.

To find out your version of Windows click the *Start* button, then RIGHT-click “Properties”. That new pop-up will give you full details about what version of Windows you are running and it will also tell you if it is 32 or 64-bit.