The developer just gave me a new version of the website to upload to the subdomain. I am setting it up, I ran this command, and it isn't working. No rake commands are working.

What is going wrong?

-bash-3.1$ rake db:schema:load RAILS_ENV=production
(in /home/admin/*****)
rake aborted!
no such file to load -- ar-extensions

The website shows:
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A source file that the application requires, is missing.

*
It is possible that you didn't upload your application files correctly. Please check whether all your application files are uploaded.
*
A required library may not installed. Please install all libraries that this application requires.

Further information about the error may have been written to the application's log file. Please check it in order to analyse the problem.

Error message:
no such file to load -- ar-extensions
Exception class:
LoadError
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