Error installing rubyMine, no SDK specified, but it is listed

ruby, ruby-on-rails, rubygems, rubymine, sdk

Solution

I went into settings and an SDK was already listed, but it wasn't until I clicked 'update gems' that everything got installed ok. Then I was able to start and use the application fine.

Problem

Getting "Could not install gems:no SDK specified" when trying to run any command such as starting the rails server. Why am I getting this and how can I get around it? I've had issues before with the JDK but not seen this SDK error.

Original source