Fix for “The exchange server (null) is not responding”

I am running Yosemite GM3 at the moment and I had difficulties adding one of my Office 365 exchange accounts to the Mail application.

The behaviour was really weird, I filled in my name and account details and it tried to resolve the server and then gave me the error “The exchange server (null) is not responding…”.

Whenever I filled in the wrong name, but the right email address and password, it would correct my name, so there was communication somehow.

To fix this:

  1. Go to “System Preferences
  2. Go to “Internet Accounts
  3. Click the + symbol
  4. Select “Exchange
  5. Fill in your account details, like your name, email address and password. BUT DO NOT CONTINUE.
  6. Change the domainname of your email address to something non existing. So in my case I changed to
  7. Click “Continue“.
  8. In the next screen correct your information to the right info and make sure that the server address is correct (in the case of Office 365, change it to
  9. Click “Continue“.
  10. Be awesome!