That sounds like you're trying to install over a newer installation already on the hard drive. If it's already installed and you still want to reinstall, make sure you delete all the old info first.
In order to remove World of Warcraft from your system, please follow the instructions below.
For Windows Users:
1) Go to the Start/Windows button, and click "Control Panel"
2) Look for "Uninstall a program" (Windows Vista/7) or "Add or Remove Programs" (Windows XP)
3) Right-Click on the World of Warcraft icon and select "Uninstall"
This will begin the uninstallation process.
If the game is not listed in the Add/Remove Programs, manually uninstall the game by deleting the folder directory where WoW was installed.
Select and Delete these folders if they exist.
C:\Program Files\World of Warcraft
C:\Program Files (x86)\World of Warcraft
C:\Program Files\Common Files\Blizzard Entertainment
C:\Users\Public\Games\World of Warcraft
C:\Users\Public\Public Documents\Blizzard Entertainment\World of Warcraft\
Then try the dvd install again.
Account and Technical Services
Feel free to rate my services at the following link: https://www.surveymk.com/s/T8S7BX2
"Valar Morghulis.....Valar Dohaeris"