1984 Courtesy of SafeScreen
I have spent 2 weeks working on this situation and would be VERY happy to be interviewed to expose the nightmare that MSFT has caused us. There are now what one would think legimitate ISP's that are using SmartScreen (in itself a HUGE oxymoron) that are now shutting off huge parts of the internet. All these same ISP's are blaming MSFT for your legit site getting blacklisted and silently accept and delete your inbound email with nary a bounce, thus a violation of RFC-822 and RC-2822.....
In my case i have thrown huge amounts of time changing DNS, implementing SPF, an anti-spam gateway, more rule and other changes than you can shake a stick at. I have been an SMTP & DNS administrator since 1984 (strange, this whole experience is very Orwellian!). we run a VERY legimitate site, and have no open relays, false DNS, or other headaches associated with the issues to hand. The end result is my 70 ++ year old parents are screwed in receiving our email, helpless to know what to do, and i and my business partner have spent more than 100 hours in the past 2 weeks, just to be continualled screwed at each new turn by MSFT. Contact me if you'd like to take your story even more mainstream -- people need to know what the Nightmare on SafeScreen street truly is!