Error extracting file modpack.jar

[Jadonsmine]

I keep on trying to fix this one modpack for my brother, "Lets see how this ends..." and it keeps displaying this error message when it finishes installing:

Error unzipping a file for the following pack: Lets see how this ends...

 

Error extracting file modpack.jar

 

Please consult the modpack author.

 

My forge version is: 14.23.5.2838

Any info is helpful.

Here is the download link: https://www.dropbox.com/s/mw1drjkxyz9rr1q/Completely%20and%20Utterly%20New.zip?dl=1