Description:

This error informs you that one of your World of Warcraft files is corrupted, inaccessible, or damaged beyond repair.


First solution:

• Launch the Firestorm launcher
  
• Choose your expansion and go to your full client folder and select it.
  
• Select "Settings" and click on "Analyze and repair"
  
• Wait for the repair to be completed
  
• Try to log in by clicking on the "Play" button.
  
  

Second solution:

• See if the error message contains: "failed to open/read file [Name of the file and its location]"
• Go to your torrent where you downloaded the client
• Right-click on the torrent and look for corrupted files
• After you it found the corrupted files redownload those files.
• Replace the corrupted file of your game with the freshly downloaded ones
• Right-click on your World of Warcraft folder and uncheck the "Read-only" property, apply the changes to the folders and subfolders
• Launch your game as an administrator

Third solution:
The error may be caused by a network problem like the one below :

"ERROR #134 (0x85100086) Fatal Condition Program: C:\Program Files\World of Warcraft\WoW.exe Unable to establish a connection to socket: The socket is already bound to an address, or the parameter is a listening socket.”

To resolve this form of error #134, refer to this.

Fourth solution:
More rarely this error will appear because of a graphic problem.

"ERROR #134 (0x85100086) Fatal Condition Program: C:\Program Files\World ofWarcraft\WoW.exe File: G:\build\buildWoW\ENGINE\Source\gx\CGxDeviceD3d\CG xD3dDevice.cpp Line: 1529 Driver internal error on resource lock. Check AGP aperture."

To solve it, update your graphics card drivers and Microsoft Direct X.

Fifth solution:

• Try to reinstall the game.