First of all if you play WoW in real servers you should make a copy of your WoW folder for private servers. Your WoW folder is normally C:\Program Files\World of Warcraft\. Make a new folder for example C:\Program Files\WoW-Private\ and copy all files from C:\Program Files\World of Warcraft\ to there. Although the copying takes alot of time don't worry. Because WoW is a huge game it will take also huge amount of time to copy.
When the copying finishes open the new WoW folder and go to the Data folder. There will be a file named patch.MPQ. Delete it. Then go back in to the WoW folder and click Repair.exe. When the screen appears click "Reset and Check files" like in the picture below.
After this download the newest patches to the Data folder for example from http://a.wirebrain.de/wow/. I recommend the Filefront mirrors since Filefront doesn't have a cap of how many files you can download and it also provides fast downloading speeds. You will need to download about 880 MBs and three files but it will be worth it!If this helped you or you have questions please leave a comment. This was my first blog so feel free to comment the layout etc! :)
