What can I do to resolve this error when trying to install bundler?

问题

I am trying to run this command

gem install bundler

but I am always getting this error:

ERROR:  Loading command: install (LoadError)
        cannot load such file -- openssl
ERROR:  While executing gem ... (NoMethodError)
        undefined method `invoke_with_build_args' for nil:NilClass

What can I do about this? I already tried this (as pointed out here 'gem install bundle' get something wrong):

rvm pkg install zlib
rvm remove 2.0.0 
rvm install 2.0.0

回答1:

it's a known issue - rubygems 2.0.0 requires openssl, run this:

rvm get head
rvm reinstall 2.0.0 --autolibs=3

回答2:

If you are using Cygwin, try to reinstall the ruby packages using the installer. Even if they are the same version.

来源：https://stackoverflow.com/questions/15392752/what-can-i-do-to-resolve-this-error-when-trying-to-install-bundler