[chef] Knife-Windows

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I'm trying to bootstrap a windows 2008 R2 Server with chef and i'm receiving
this error

:"CScript Error: Execution of the Windows Script Host failed. (0x800A0007)".

After some research i find out that i must install the "specific_install" gem
and use Knife-windows gem from git but when i'm trying to install gem with 
this
command

"gem specific_install -l https://github.com/opscode/knife-windows.git";

i'm receiving the following error :

"ERROR: While executing gem ... (NoMethodError) undefined method `build' for
Gem::Package:Module"

What am i doing wrog?

Thank you in advance