If you encounter any errors while installing World of Warcraft: Wrath of the Lich King, please check your DVD to verify that it is clean and scratch-free. Even the smallest scratch or bit of dirt can prevent your DVD-ROM drive from reading the disk. If your disk is clean and scratch-free, please try the steps below to see if they resolve your error.
1. Shut down any background or antivirus programs: Antivirus applications can interfere with installers on some computers. Please shut down all current applications and try running in a selective startup to see if you are able to complete your installation successfully.
2. The installer program will try and access the internet to determine if there are any updates available, please make sure it is allowed to connect in any firewall or similar security software.
3. Try the disk in a new drive: If you have another DVD-ROM drive in your computer, try inserting the disk into that drive to see if you can successfully install the game from it. Some drives are able to read damaged disks more easily than others.
4. Contact Blizzard Entertainment: If you are still receiving errors during the installation of World of Warcraft: Wrath of the Lich King and you are unable to complete the installation, please contact Technical Support for further instructions.