GetComponent on iOS?

Hi. When I am trying to affect the public variable “ABC” in the script “TEST”. This piece of code works perfectly when the current platform in Unity is set to Windows/Mac. But when I try to develop for iOS, I get the error " ABC’ is not a member of 'UnityEngine.Component". What is wrong? Thanks

MyObject.GetComponent("TEST").ABC=1;

Never use quotes in GetComponent; that makes it return Component instead of the type, plus it’s slower.