Exchange Server is run by your IT staff so my advice is to call them up and ask them to fix this.
There are issues with MSN email as Microsoft continues to close it down in favor of their Live email system. But your IT staffer should tell you if you are affected.
Bob
I have an iPhone 4 and for some reason my exchange account is not moving my MSN to my inbox, it's telling me the password I'm using is incorrect, how do I reset my password?

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