> If people start with "Hi, I have a problem" and don't state what the problem is I just respond with "drop me the details and I'll have a quick think" and get back to my work.

If people start with "Hi, I have a problem" and don't state what the problem is I close the chat window.

My work IM's status clearly states "if you have a question, ask it, don't ask if you can ask", time wasters simply get ignored.

> Some problems require a more urgent response so I'll accept a walk-up or a shout for those

Absolutely.