Black Ops II - Zombies Help

It keeps saying that my Zombies needs a update and it's been like that for 2 to 3 days now, and I don't want to uninstall MP and Zomnies again...

Error is Uppdate required.

Uninstall it, download it, then verify game cache, it worked for me.

1.Go to /c/Programms(x68)/Steam/SteamApps/common/And Copy'n'Paste the Call of Duty Black ops 2 File anywhere you want (Steam needs to be Off)
2.Then Start Steam again,Uninstall Zombie,MP,Singleplayer.
3.Install Everything Again.
4.Verify Game Cache Like Birdpoop Said.
5.And Everytime it wants to Download Again Just Delete The File that he want to download again and but the copy'n'paste thing there. but u have to use the copy'n'paste file right after it want to Download. Hope i Helped