For those of you arguing that entrepreneurs and salespeople must always be available, I present to you Exhibit A. While this is specific to Yesware (and you should check out their other OOO examples), it's easy enough to tweak to fit your industry.
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Oh you see, I do that on purpose. That way I can use the same OOO message internally and externally. Anyone within our company can find us in the global address book. Anyone outside our company who has done business with my department has my email address & my manager’s.
I read it as coming from a person who was overly frustrated with their regular OOO being ignored. It’s one of my pet peeves – the OOO clearly says I’m not there and to contact Bob, yet the sender continues to reply, never contacts Bob, then blows up at me when I return that their work is delayed. I would love to be able to send something like this message in the letter but it wouldn’t fly at my office.