Why does it take so long to receive an email?
Our servers are configured with multiple layers of software for the purpose of identifying and minimizing the amount of spam related email coming to your email accounts. Statistics indicate that the vast majority of emails on the internet are unsolicited spam.
If you are experiencing perceived delays receiving emails, it may be related to "greylisting". Greylisting is the technique of denying mail delivery the first time a sender tries to deliver to a recipient. The next time the remote server attempts to deliver the message, it is accepted. Future messages from the sender to the recipient are then allowed. With Graylisting enabled, our mail server will "temporarily reject" any email from a sender it does not recognize. The originating server will try a new delivery, usually in a few minutes, and if the mail is legitimate, it will be accepted.
If the mail is from a spammer it will probably not be retried, as spammers go through thousands of email addresses and cannot afford the time delay to retry a particular message. Standard mail servers, however, always attempt to deliver messages again if they are rejected with such a “temporary” error message, in accordance with the SMTP RFC specifications.
Switching off greylisting is an option but we highly recommend not doing so as it could result in a significant increase in unsolicited mail.
For a more technical explanation of greylisting see: Wikipedia Article: Greylisting