ERROR: Mixed source of plugins, you can't mix local `.gem` and remote gems

Hi,
when i execute below script
plugin install C:\analysis tools\logstash-2.1.1\bin\logstash-input-mongodb-0.3.0.gem

getting error
ERROR: Mixed source of plugins, you can't mix local .gem and remote gems

in command prompt. i am trying to achieve import data from mongodb to logstash.
I am referring below link.


thanks in advance.