# Rails on Mac OS X Leopard **URL:** \ **Category:** Rails\ **Created:** [March 17, 2008, 5:14am UTC](https://www.ruby-forum.com/t/rails-on-mac-os-x-leopard/132116 "2008-03-17T05:14:06Z")\ **Posts on this page:** 4\ **Page:** 1
**Author:** ![nahabed](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/b77776/32.png) [@nahabed](https://www.ruby-forum.com/u/nahabed)\ **Post date:** [March 17, 2008, 5:14am UTC](https://www.ruby-forum.com/t/rails-on-mac-os-x-leopard/132116/1 "2008-03-17T05:14:06Z")
[I posted this earlier today but it didn’t show up on the list so i am reposting. Pardon if you seen this already] A few days ago I got a new Macbook Pro (yippie!). Until now, I was using Instant Rails on Windows. I am now trying to get my rails projects to run on the MBP having copied them from Windows. From the terminal window, I can see that Rails and Ruby are installed as advertised (–version works). For now, I am happy with Ruby 1.8.6 and Rails 1.2.6 that are on there. HOWEVER, when I try “ruby script/ server” or “ruby script/console” I keep getting the following error. Cannot find gem for Rails ~\>1.2.3.0: Install the missing gem with ‘gem install -v=1.2.3 rails’, or change environment.rb to define RAILS\_GEM\_VERSION with your desired version. What am I missing? Isn’t all the “basic” stuff preinstalled out of the box? The project I am trying to run is very simple - no fancy gems or anything. It was also built using 1.8.6 I read this [http://developer.apple.com/tools/developonrailsleopard.html](http://developer.apple.com/tools/developonrailsleopard.html) but its trying to get me to update and I’d like to stick to 1.8.6 and 1.2.6 since some of my other projects are based on that. Thanks, Roupen N. ---
**Author:** ![nahabed](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/b77776/32.png) [@nahabed](https://www.ruby-forum.com/u/nahabed)\ **Post date:** [March 17, 2008, 5:24am UTC](https://www.ruby-forum.com/t/rails-on-mac-os-x-leopard/132116/2 "2008-03-17T05:24:38Z")
nahabed wrote: > Cannot find gem for Rails ~\>1.2.3.0: > Install the missing gem with ‘gem install -v=1.2.3 rails’, or > change environment.rb to define RAILS\_GEM\_VERSION with your > desired version. Just do what the message tells you: - either install version 1.2.3 with the provided gem command - or change the dependency of your application to the installed 1.2.6 ---
**Author:** ![nahabed](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/b77776/32.png) [@nahabed](https://www.ruby-forum.com/u/nahabed)\ **Post date:** [March 17, 2008, 5:29am UTC](https://www.ruby-forum.com/t/rails-on-mac-os-x-leopard/132116/3 "2008-03-17T05:29:23Z")
nahabed wrote: > Cannot find gem for Rails ~\>1.2.3.0: > Install the missing gem with ‘gem install -v=1.2.3 rails’, or > change environment.rb to define RAILS\_GEM\_VERSION with your > desired version. That’s the key. It means that your application has defined the rails version to use in config/environment.rb, which is rails default behaviour when you create a new project. I’d ignore the gem installation and instead update the environment.rb file (or you can set the RAILS\_GEM\_VERSION environment variable to “1.2.6”) Find the line in that file that reads: # Specifies gem version of Rails to use when vendor/rails is not present RAILS\_GEM\_VERSION = ‘1.2.3’ unless defined? RAILS\_GEM\_VERSION and change it to read: RAILS\_GEM\_VERSION = ‘1.2.6’ unless defined? RAILS\_GEM\_VERSION and all should be well again. Mac ---
**Author:** ![nahabed](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/n/b77776/32.png) [@nahabed](https://www.ruby-forum.com/u/nahabed)\ **Post date:** [March 17, 2008, 9:12am UTC](https://www.ruby-forum.com/t/rails-on-mac-os-x-leopard/132116/4 "2008-03-17T09:12:24Z")
That fixed it - thanks 🙂 On Mar 16, 9:29 pm, Paul M. [removed\_email\_address@domain.invalid](mailto:removed_email_address@domain.invalid)