Anyone familiar with Outlook in a corporate setting?

[Taxminion]

Work for a large organisation. I suspected someone was accessing my email today and asked a colleague to try and open my inbox, unfortunately my settings were wrongly set on my main inbox so anyone could access it. I strongly suspect it is my manager.

I don't think I have any basis for referring as a security incident which would presumably mean the administrators could do an audit trail. Is there any way of me checking who might have accessed it - I can't see anything that would allow me to do it.

I think it is a basis for a security incident. At best it means IT needs to send out instructions on how to set up Outlook properly and review their default settings.

You suspect that your boss did it but maybe not. If I was attacking your business externally I would try to make it look internal too. Tell the IT Admin if only to be absolutely sure your company is safe.