I had the same error as others here. I was trying to install JRuby and kept getting

ERROR: Error installing mime-types-data: mime-types-data requires Ruby version >= 2.0

From this page I got that JRuby doesn't use the version of ruby you might think it does. So you can check what it's using by doing:

jruby -v

The version of Ruby is in brackets. Then to upgrade the version of Ruby being used I got a tip from this page which said to add an env var:

set JRUBY_OPTS=--2.0

All working better now, well no error anymore!

I had the same error as others here. I was trying to install JRuby and kept getting

ERROR: Error installing mime-types-data: mime-types-data requires Ruby version >= 2.0

From this page I got that JRuby doesn't use the version of ruby you might think it does. So you can check what it's using by doing:

jruby -v

The version of Ruby is in brackets. Then to upgrade the version of Ruby being used I got a tip from this page which said to add an env var:

set JRUBY_OPTS=--2.0

All working better now, well no error anymore!