I recently discovered that I was occasionally missing emails from correspondents.  Reviewing the emails, it is obvious how they could be construed as SPAM (one sentence with a URL) however these are from regular correspondents, who are unlikely to be spoofed in a from address, so I searched out a way to whitelist them in IMF.  Unfortunately, Microsoft has decided that spoofing is too easy, and the only means of whitelisting is by IP address.  This doesn't really solve my problem, so I started looking in to other solutions.  There seem to be a couple of options often mentioned, IMFcompanion and IMF Tune.  IMF Companion is freeware, however it hasn't been developed since January 2007.  Several reports in online forums says that it doesn't whitelist as well as it should.  IMF Tune is a commercial application which realistically isn't that expensive, but is expensive enough that I could get Hosted Exchange accounts for less money.

Vaguely frustrated by the experience, I decided I would have to write something.  I had heard of SMTP event sinks, and started doing some reading.  Most of the articles are of the "add a disclaimer" type, and nothing led me to believe that I could force IMF to bypass a message check based on a set of criteria.

Quite a while ago, I had read about the FileSystemWatcher class in .NET.  I researched it when reading about FolderShare.  The way I have IMF configured, SPMA messages are archived, and can be delivered by plopping them in the pickup directory of the SMTP queue.  I thought that a Windows service which watches for new messages, compares the From: line with a whitelist, and moves them from the UCEArchive directory to the pickup directory if they aren't SPAM should work fairly well.  I hope to have something written soon, and will potentially release the source here.  Thanks for C# Corner for their article on Creating Windows Services and Code Project for their hints on debugging a service.

This kind of thing has been difficult on the MacBook.  I really should create a Visual Studio VM, but for now I'm coding on my work laptop and via remote desktop to my XP desktop at home.  It works ok, but isn't brilliant.