Warcraft Version Switcher is a software which enables you to have both 2 versions of warcraft on 1 PC.  We have pre saved 2 versions in the version switcher : 1.24 and 1.24b.

Download Warcraft Version Switcher.

Readme:

-Click on the 1st icon: Switch Version.
-Double Click to Select the version you want to use.
-Click on Frozen Throne Icon to launch game.