I have two sites - one on a Windows server which allows you to register/login as a user and another which functions as a normal site (though does include a contact form) on a Linux server.
The first Windows site seems to be delayed in sending confirmation e-mails but to my GMail addresses and work e-mail it does send eventually (though I'd rather this be instantaneous.)
A colleague wishes to login/register using his work e-mail but did not receive such e-mail. I used a 'test e-mail' sender on the Linux site to his e-mail and still has not received anything (it worked with my work e-mail instantaneously). I thought this was a server issue but now I'm not sure what it could eb.
I know this isn't exactly WordPress specific but I'm wondering if it is to do with WordPress itself or if there are any other reasons why this might be the case?