iCal sending invitation from no longer existent email alias. How can I fix that?

I've had my me.com email account for almost 4 years now. Of course I've been using iCloud for the past year. The only issue I have at the moment is with my iCal invitations. I used to have an email alias that I no longer use but have deleted it a long time ago. Now when I sent iCal invites recently, people got it as if they were sent from my old alias. Could someone please tell me how to make the invitations be sent from my actual email account?

Thanks!!