It has been my policy to answer every email received. Unfortunately 
over the past three years I have become aware that many of my 
incoming and outgoing emails (including those registered as sent), 
have not been received. Even emails from one of my addresses to anothr have been blocked.

At a recent conference I asked if others had 
experienced the same problem, and a number of people raised their hands.
I am therefore inviting anyone who did not receive a reply to write 
to me again, at pdscottweb@hotmail.com,  and to persist until you 
have heard from me.

To judge from this  article by Wayne Madsen,
the problem may be due to Internet censorship under the Patriot Act. 
(As a former employee of the National Security Agency, Wayne Madsen 
writes with some authority.) I recommend therefore that in an email 
inquiring about possible non-delivery, no dangerous subversive words 
(like "protest") be used.