ICS Update to 4.0.4 has broken Email

My first Android phone, my first OTA upgrade and it's broken the email app.
Everything else looks to be working.
Galaxy S2, turned it on, it downloaded, it updated and then rebooted. Now any attempt to open Email and I get a message saying "Unfortunately, Email has stopped"
I'm getting notifications of new mail, just can't run the app.
So, all you experienced Androiders, what is a Windows man to do now, I haven't a clue?

 

Thanks, I've done that and now installing everything from fresh, I hope this isn't normal ;-)