Print Friendly VersionGreylisting is a new tool in the fight against spam. What it does is temporarily block incoming mail from a sender. It returns the mail to the sender's mail server with a message saying try again later. The sending server must then retry sending the mail after the Block Period but before the Pass Period (see below for definitions of these values).
Greylisting is effective because spammers will not usually bother to attempt a second delivery, but legitimate e-mail servers will.
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.
How do I turnGreylisting on or off?
In order to turn Greylisting on or off, sign in to your Webmail. Click Settings > My Settings > check or uncheck the Bypass Greylisting option.
What are Go Web's Default Settings for Greylisting?
- Block Email with Greylisting - Greylisting is automatically enabled when your email account was created. If you want to turn Greylisting off, follow the instructions above.
- Block Period - Go Web's Block Period is 5 Minutes. This is the number of minutes that e-mail will not be accepted.
- Pass Period - Go Web's Pass Period is 360 Minutes. This is the number of minutes in which the sender's mail server has to retry sending the message.
- Record Expiration - Go Web's Record Expiration is 36 Days. This is the number of days that the sender will remain immune from greylisting once it has passed.
Disadvantages of Greylisting
The biggest disadvantage of greylisting is the delay of legitimate e-mail from servers not yet verified. This is especially apparent when a server attempts verify a new user's identity by sending them a confirmation e-mail.
Some e-mail servers will not attempt to re-deliver e-mail or the re-delivery window is too short. Whitelisting can help resolve this.