Solution: You won't get key from steam, There is one and only way, follow steps given below

1) Login to your EA origin account
2) Go to EA help section
3) Select live chat
4) Tell them you are unable to play multiplayer and request them to add base game in your origin account
5) They will ask 2 screenshot, one from your purchase history (you can find in your profile page -> Top right click on your name -> account details -> View purchase history), second screenshot is from your purchase successful email, keep these screenshot ready
6) Once the base game gets added to your origin, now you can play the multiplayer

Solution: Update PunkBuster to latest

Solution: Make sure you have this game in your EA origin library, if not follow the above solution,
Important Note: Don't check "Remember Password" and "Auto Login", you have to login everytime you open game

Multiplayer servers have no active players, buy this game only for single player story mode and also Vietnam DLC is only for multiplayer, it doesn't have story mode.

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