The curse of the validation email strikes again. I've just installed 5.1 on GoDaddy.com today and all aspects of sending emails are working except the sending of the validation email.
I've searched the forums and I see others have had this problem too, and I also see that the issue basically poo-poo'd as a PEBKAC issue. Sorry, frustration is getting the better of me, I know the like of Gary and Rick are always helpful where possible.
Anyway, it would be really great if someone might at least give some suggestions as to what the problem might be. I've experienced it now with two different versions of Tiki and two different host providers (the original host was AFMU for what it's worth). I'm thinking it's a host issue but then surely no email would be able to be sent, why only the validation email? What's so special about the validation email?