Error 134 may appear slightly different but in general they fall in to 2 areas, we have previously mentioned that some Error #134s are quite similar to Error #131 so if you are getting that kind of error consult the section on possible solutions to Error #131.
One of the more common Error 134 errors may appear as follows:
ERROR #134 (0x85100086) Fatal Condition
Program: C:/Program Files/World of Warcraft/WoW.exe
Unable to establish a connection to socket: The attempt to connect was forcefully rejected.
If you are getting this error it is usually an indication that you have a firewall or some form of Firewall software installed that is not working correctly with World of Warcraft. Even if you have previously configured your security before problems can occur, most often after a new patch has been applied.
Depending what type of firewall you have you may need to consult any previously configured firewall software and remove all entries for World of Warcraft and re apply them again to clear the error.
As a general note World of Warcraft requires TCP port 3724 open to ensure the game functions correctly.
You can find more information on how to configure your firewall/ with some of the guides we have on our F.A.Q Website:
Norton Internet Security:
Configuring Norton Internet Security for World of Warcraft
Reconfiguring Norton Internet Security after a patch
If you are not able to locate your firewall or security software please consult the documentation that came with your security software or contact your manufacture.