Give this a shot... http://www.blizzard....w/?id=aww01635p
However on that page ignore the paragraph that says
"If the installation hangs or gives an error at the same point or on the same file every time, it's possible the CD itself is damaged on the sector where that file is stored. Try the disk in an alternate drive or even an alternate computer to see if the same problem happens. This is the easiest way to identify a potentially damaged CD."
Ignore it because if you tried both WoW and WC3 and both gave you same error, it is highly likely it isnt both cds are corrupted.
Sounds more like your administration with windows may be compromised, and it wont let you install stuff, so instead gives you errors.
Try this also.
DMA if Available ( Windows 2000/XP )
Open the System in Control Panel.
Open the Device Manager under the Hardware tab.
Double-click the IDE ATA/ATAPI Controllers category.
Next, double-click each IDE channel that is present and make sure that "DMA if available" is selected under the advanced settings tab.
Reboot your computer.
Edited by AitrusSkyy, 29 July 2006 - 04:54 PM.