Seems to be a problem with exchange addresses containing an apostrophe so probably needs a fix from Apple.
Techradar: "Emails don't appear in iOS 10 Mail app
If you're using iOS 10 and you open up the Mail app, you may be greeted with a blank screen. A number of iOS 10 users are reporting this problem, and they all seem to have one thing in common: having an apostrophe in their email address.
It appears that a bug in iOS 10 is preventing the Mail app from showing these addresses. So, if you do have an email address with an apostrophe in it, you'll have to wait for a fix from Apple. In the meantime, if you have other email accounts you can make emails to those addresses appear by removing the mail account with the apostrophe from the Mail app. The other email addresses will now appear.
Many email accounts let you forward mail to another email address, so until a fix is released you could set emails that go to your email address with an apostrophe to be forwarded to another address. The process for this varies depending on the email provider, so visit the website of the company that supplies your email address for more information."