Outlook 2013 email tracking to CRM 4.0 error

Hi,

since upgradign to Outlook 2013 I can no longer track emails whilst in the 'create message' window. When I try to send the email it says

'E-mail cannot be sent because the specified sender does not have an e-mail address. Add an e-mail address to the sender and then try again. do you want to send the e-mail? If you click yes, the e-mail will be sent out, but no corresponding activity will be created in Microsoft Dynamics CRM'

I have checked my user profile in CRM and this has my primary email filled in correctly. can we resolve this or am I doomed to forever have to track emails after sending them?

thanks,

Jennifer