Overriding C# Conditional statements problem

I was writing some code today and something was not working as I expected. Why does the following code execute even though the condition should have evaluated to false? alt text http://img215.imageshack.us/img215/3011/agfewrf.gif I have tried putting braces around the two conditions, and switching their position, but the EndedUsingApplication even still executes. EDIT: It has nothing to do with the || or && operators. Look at this... Nobody can learn from my mistake unless I post the culprit code, so here it is. ``` public static bool operator ==(ActiveApplication a, ActiveApplication b) { if ((object)a == null || (object)b == null) return false; return a.process_name == b.process_name && a.window_title == b.window_title; } public static bool operator !=(ActiveApplication a, ActiveApplication b) { return a == b ? false : true; } ``` And here is the working code ... ``` public static bool operator ==(ActiveApplication a, ActiveApplication b) { // Casting to object class prevents this comparison operator being executed // again and causing an infinite loop (which I think .NET detects and stops // but it would still be a huge hole in the logic. if ((object)a == null && (object)b == null) return true; if ((object)a == null ^ (object)b == null) return false; return a.process_name == b.process_name && a.window_title == b.window_title; } public static bool operator !=(ActiveApplication a, ActiveApplication b) { return a == b ? false : true; } ``` The problem appeared to be when the != operator received two null values.