This error occures when RK can't find Warcraft III on your system.
Copy RK in your Warcraft 3 main folder and run it there. DONE
If the error stays, contact me!
Drag the Frozen Throne.exe file and drop it on ReplayKit.exe. Now there should pop up a message that the new path was saved. When this has happened, run RK again and everything should work now! DONE
Write the required registry keys urself. This is done by following one of the two guides beneath.
Write in the command line regedit to open the registry editor.
First navigate to 'HKEY_CURRENT_USER\Software\Blizzard Entertainment\Warcraft III'.
Then use on that key rightlick -> new -> string value and name it InstallPath. Afterwards open the string via rightclick -> modify and insert the path of your Warcraft III, for example: C:\Program Files (x86)\Warcraft III
If you prefer a video guide, check this out, it's exactly the same:
http://www.youtube.com/watch?v=cVzIzBFtVXo
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