Cannot load file Rails

LoadError: cannot load file

Quick Answer

Ruby can't find the file to require.

Why This Happens

In Ruby on Rails, ruby can't find the file to require. This is one of the most common Ruby on Rails errors developers encounter. Understanding the root cause helps you fix it quickly and prevent it from recurring.

The Problem

require 'nonexistent_gem'

The Fix

# Add to Gemfile:
gem 'nonexistent_gem'
# Then: bundle install

Step-by-Step Fix

  1. 1

    Identify the error

    Look at the error message: LoadError: cannot load file. This tells you exactly what went wrong.

  2. 2

    Find the cause

    Check the stack trace to find which line of your Ruby on Rails code triggered this error.

  3. 3

    Apply the fix

    Use the corrected code pattern shown above. Test to confirm the error is resolved.

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