Best and Safest Way to Self-Hosted Mail

Connecting Outlook to an Exchange Server is great.  Not only is your mail synchronised on all your devices, but so are your contacts, calendars, and tasks.

For small numbers of staff, it may be cheaper and wiser to have your Exchange server hosted by someone else, but as your staff numbers grow it can become cheaper and faster to host Exchange yourself.

When you host your own mail server (Exchange or otherwise), you need to allow anyone to send mail directly to your server over your (probably ADSL or cable) internet connection.  This presents a problem.  If some rogue computer starts flooding you with email, your internet connection can become swamped, causing problems for your business – especially if you’re using VoIP.

A good solution is to have your public-facing mail server hosted by someone else.  Then this mail server can scan all your mail for viruses before forwarding it to your own mail server at your office.  You can set your firewall to only expose your office mail server to your external mail server, thus preventing the world from being able to access your mail server directly.  Furthermore, the external server can store and forward your mail should your own server, internet connection, or power fail.

The well-known DNS hosting company DynDNS offer a mail relaying service, called MailHop Relay, and it’s very good value.  I have found it to be perfectly reliable with only two minor complaints.  Firstly, incoming attachments are limited to 10 MB.  This is quite quite justifiable for a number of reasons, especially given the price of the service offered, but is none the less seen as a drawback by users.  Secondly, DynDNS offer an elegant control panel enabling various virus and spam blocking services to be enabled or disabled.  Unfortunately, the “Reverse DNS” test – which is a highly effective spam-blocking mechanism – is not respected by the “whitelist” feature.  Therefore, if you ever have a single valid sender fail the Reverse DNS test (which is inevitable really), then you cannot whitelist them and therefore are forced to disable the Reverse DNS test and allow through some of the spam which would otherwise have been caught.  I have pleaded with DynDNS to correct this feature, and although they were responsive, they were unwilling or unable to make this change.  (In fact, they tried to argue that it makes sense the way it is).

But those two minor drawbacks aside, DynDNS’ MailHop relay is otherwise excellent.  It is much better to have your mail filtered by an external server and stored on your behalf should your own server become unavailable, and it also reduces the potential for flooding of your internet connection and internal mail server as well.