Cannot get mail on a new iPhone?

You just got your new iPhone, configured your Exchange email, everything seems OK until you actually try to retrieve mail from the server.
All of a sudden, you get a message saying:
"cannot get mail the connection to the server failed"

You tried everything: 

• deleting the account and recreating it
• restarting your phone
• changing different "Period to sync" settings
• 3G vs WiFi connection
• Even resetting your phone

Well, if you tried all of the above, then it's time to log in to Outlook Web App.

Go to Options->See all options->Phone->Phones

You should see a list of all the mobile devices you used with ActiveSync for your Exchange account.

Now, if there's already 10 in the list - there's your problem. 

Just delete one of the existing and not used devices and the mail will suddenly start to appear on your new iPhone.