What should I do? (DOTA 1.24 can not update it.) Help?

When I run the program this is what happened: Blizzard prepatch compiled v2.70 On July 7 2003 This program patches warcraft 3 record set at 11:25 AM on 09/16/2009 Error loading registry key 'Warcraft III The InstallPath' system can not find the file specified. RESULTS: Prepatch not Please help me! Thx