Spam prevention

Recently we had some problems with our DNS provider for the business which caused us to look at moving the domain over to another more reliable provider.  In the end we decided to settle with hosting the DNS with pipex and while they may not have always had the best reputation they are one of the larger players, considering the problems recently meant that we had no email or website traffic we were not able to get caught with that again.  All went well with the transfer as I made sure that all of the DNS records were live before the actual transfer took place so the transition was completely seamless.  However, since then it would seem that the spammer capitalised on one oversight that I made during the transfer; this was SPF (Sender Policy Framework).  For those that don’t know what this is basically it is a TXT record within DNS which defines the hostnames and/or IP addresses which can receive and send mail for the domain name it applies to.  This TXT record is read by any mail server that can support it and should the email not have originated from the correct address then it is treated as spam and discarded as such.  If, however, the mail originates from a valid address then it is processed as normal and passed on to the recipient.  On the other hand if the recipient mail server does not support SPF then this information is simply ignored.  Since I hadn’t got this information handy I was tasked with re-creating the SPF data which for those that have looked it is not the most straightforward thing to do however Microsoft have very kindly created a wizard on their website which takes out most of the work.  The address is as follows: http://www.microsoft.com/mscorp/safety/content/technologies/senderid/wizard/

Using this wizard you are able to enter your domain name and it will process the DNS record to see what settings exist with regard to mail servers and then guide you through the process of creating the SPF data.  Over the past few years I have using a number of tools but this has to be the easiest to follow.  So check it out, the more people that use SPF the less spam will be possible.

As always thanks for reading and if you have any questions then drop me a line.

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