Question

I have a simple Rails application I want to deploy to Heroku. When I run the below command

git push heroku master

The below error message is displayed.

 Could not find multi_json-1.3.1 in any of the sources
 !
 ! Failed to install gems via Bundler.
 !
 ! Heroku push rejected, failed to compile Ruby/rails app

Here is my Gemfile

 gem 'rails', '3.2.3'
 gem 'pg'
 group :assets do
  gem 'sass-rails',   '~> 3.2.3'
  gem 'coffee-rails', '~> 3.2.1'
  gem 'therubyracer', :platform => :ruby
  gem 'uglifier', '>= 1.0.3'
end
gem 'jquery-rails'

Answer 1

Delete the Gemfile.lock file, and run bundle install.
This works for me!