One of the spam filtration tactics the majority of hosting companies use including Foremost Media is greylisting.

What that means is that each time a given mailbox on our email servers receives an email from an unknown contact (ip), that mail is rejected with a "try again later"-message (This happens at the machine level and is transparent to the end user- in other words our mail server asks the sending mail server to resend the message). This means that all mail gets delayed for a matter of seconds until the senders email server automatically tries to deliver it again. Most legit mail servers are set up for this and try again in a few seconds- where most spamming software will not try again later.

Why use Greylisting?

Greylisting is a very effective method of spam blocking that comes at a minimal price in terms of performance. Most of the actual processing that needs to be done for Greylisting takes place on the sender's server. It has been shown to block upwards of 95% of incoming spam simply because so many spammers don't use a standard mail server which will do automatic retries.

Can I turn off Greylisting?

While logged into your web admin panel there is a check box to enable/disable greylisting. If checked, this will allow users to selectively turn off Greylisting (useful if you have an account that receives time sensitive mail)


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