while executing gem ... (ArgumentError) unknown encoding name - CP720 [duplicate]

Question

I got now this strange error

while executing gem ... (ArgumentError)
unknown encoding name - CP720

When I want to run any gem commands such as

   gem install rubygems-update

so when I goggled it I found some one suggest to use this commands to Change encoding to 1252

C:\DevKit> chcp 1252
c:\DevKit> ruby dk.rb init  

but after I used it I still got the same error , so how i can solve this issue ?????

Note : I'm using windows 7

Answer 1

When did you do

chcp 1252

did you get

Active code page: 1252

as a confirmation?

If not then maybe you are not using one of the windows command prompts like the default one or the node.js command prompt.. Because this won't work on the Git command prompt (MINGW32).

After you get the confirmation of changing the code page, you can execute gem commands without the annoying unknown encoding name error.