Change error messages?

How do I change the error messages for users with no permissions to play?

I want to change the below error message to something telling them that they need to register to play.

Default error message is below

"The administrator has disabled viewing of the arcade for your member group. If you feel this is a mistake please PM an administrator and let them know."

Resolved: Found it in lang_Arcade_en.php I searched all files before but must of misspelled a word.