When i cloned one repo to my local disk and try to rake clean-> rake install[theme-name]-->rake preview, I encountered the issue ‘Could not find… Run bundle install to install missing gems’,
so i run bundle install in the octopress directory, try to run rake -T to show the command rake related after bundle install

is completed,then i encountered: ‘rake aborted  You have already activated rake, but your Gemfile requires rake 0.9.2. Using bundle exec may solve this.’ It seems the version of rake is conflict. i executed below steps to slove this issue:

$ gem list (to show all the gems and their version installed(will see more than one versions for rake)), and i got:

*** LOCAL GEMS ***
rake (, 0.8.7)
here it is...

$ gem uninstall rake (since the version conflict, need to uninstall one version)

Select gem to uninstall:
 1. rake-0.8.7
 2. rake-
 3. All versions

and i type into: 2 (select the version you want to uninstall, it depends the rake verison your Gemfile requires)

You have requested to uninstall the gem: rake-
addressable-2.2.6 depends on [rake (>= 0.7.3)]
If you remove this gems, one or more dependencies will not be met.
Continue with Uninstall? [Yn]  Y
Successfully uninstalled rake-
INFO:  gem "" is not installed

Now i can preview the installed theme happily…