i already make a site , but when a new user want to register using yahoo.com , hotmail.com , it didn't sent the activation code . but if the use use another mail like yahoo.co.id , gmail.com , it sent the activation code . can anyone solve my problem??
Did your users check their spam / trash folder?
yes , they already check their spam folder , i already test it with one yahoo.com mail, it have some problem . you can test too if you don't believe me .
You will have to contact Yahoo, nothing really we can do here, sadlly
Get off a host that blacklisted.