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I recently sent an email to a professor asking him about an administrative problem I was having, but after I'd hit the send button, I realized I'd forgot to say: "Sorry to bother you" or something of that sort in the beginning... Now I'm wondering is that considered impolite? Shoud you apologize to professors for bothering them or does that just make you sound phony? I greeted him with"Dear Professor X", told him who I was, asked the question, and thanked him in advance. He answered my question and all, but I'm just asking for future reference.