Error “'Validate_default_type!': An option's default must match its type (ArgumentError)” when running Ruby on Rails generate on Windows

Question

I am following this tutorial and have just started. I have installed Ruby on Rails with gem install rails and have created a blog with rails new blog

Answer 1

I have had a similar issue tonight with Thor 0.19.2.

Here is what worked for me. Please ensure that you backup all data. I am very new to Rails, so I don't know what the consequences of this will be.

First, you need to remove Thor 0.19.2.

gem uninstall thor

Type 'Y' when it asks you confirm removal. Then, install the previous version of Thor.

gem install thor -v 0.19.1

You might get an error about being locked to 0.19.2 - go into your project's gemfile.lock, and find the line containing Thor. Change 0.19.2 to 0.19.1.

You might need to restart any terminal windows you have open. Good luck!