project file not working?

As a youtuber who frequently provides projects, the simplest thing to do is to post a comment on the video pointing out the project is empty.  If they don't respond (in fairness to them, they may have thousands of comments) you can always send them an email by going to their channel's About page and looking for the For Business button.

As others have said, it is likely an issue of versions numbers.  How old is the video and what version of AE are you running?

If you open an AEP file in After Effects and there is nothing in the Project Panel then the project is nothing but an empty file. If there is something in the Project Panel but you cannot open a comp then the AEP only contains references to source files and/or solids. 

My first guess is that you downloaded an empty AEP project file. 

You need to check the version of the project created. You open the project with the same version of After Effects.

Where did you download it from?

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