I can't get my Cata WoW to open

I'm hoping someone can help me. When I click on the WoW icon to start up my Cataclysm file I get this message:

The application has encountered a critical error:

The system cannot find the file specified.

Program: C:\Users\Evey\Downloads\World of Warcraft - Cataclysm 4.3.4 (15595)\Wow.exe
ProcesssID: 9324
File: .\Client.ccp
Line: 3623

file: signaturefile

Press OK to terminate the application.

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I also get the WowError pop-up box and try sending it with the message of "Game won't load, or All I did was click to load the game." However, when I click send it never connects... It always says "Can't connect to server: A connection attempt failed because the connect party did not properly respond after a period of time, or established connection failed because connected host has failed to respond."

I don't know how to fix this, do I need to go to the original zipped file and extract all the files again?