An error was detected while verifying the contents of the file "C:\Program Files\World of Warcraft\Data\common.MPQ".
There may be a problem with your system, or with the drive at C:\. You can attempt to install again. If this problem persists,
please contact Blizzard Technical Support.
Never at the same spot one time it may be at 6% or as high as 35%.
I have tried taking the files off the disk and I have tried installing in safe mode I have even tried downloading the game from the website.