I've noticed a trend with HOTMAIL and YAHOO accounts when people register.  Sometimes the validation emails get sent, other times they are never received.  I've had one on one conversations through email with these users and validated manually but when this happens it's always HOTMAIL and YAHOO.  Anyone else notice this on their site?  Anything I can do?

i have the same problem! why?

So you know for a fact your email server is attempting to send them but get rejected by Yahoo or hotmail? Is SPC and DKIM setup? 

 

 

Isn't email fun? Lol

Have your web host check the mail server logs for those addresses which are having trouble, they will be able to provide you with the results and let you know if they were actually delivered (and sitting in a spam folder likely) or if they were rejected when sent. If yahoo and hotmail are blocking your server (which is common) then they will be able to see this in the mail logs. If they are being blocked, your web host will need to follow up and clear up any issues which resulted in the block.  This could be as simple as you are missing proper SPF and/or DKIM records or something such as your servers IP being blocked for a bad reputation of sending spam etc.