I've noticed that I don't receive my own posts to the Ohio-Birds mailing list, and once and a while, I receive duplicated posts from others. Sometimes the poster will mention that they tried posting previously, but the message disappeared. At least some of this is resulting from the way some internet service providers handle spam. As I understand it, in the early days, spammers would send mass mailings using a single "From" address. ISPs soon learned to intercept huge blocks of mail originating from a single source. The spammers adjusted by creating little macros that automatically replaced their own address in the "From" line with the address in the "To" line. The ISPs co-evolved to intercept any message with the same address in the "To" and "From" line. This tactic makes problems for mailing lists. When the mailing list distributes the post to all the subscribers, the post that is going to the original contributor will have the same address in the "To" and "From" line. Hence some ISP will delete it as spam, and it will never reach the original poster. I've learned to wait a few minutes after posting, then check the Ohio list at www.birdingonthe.net. If my post is showing up there, I can know it made it to the other subscribers. Happy birding, Paul Paul Gardner Columbus, OH ______________________________________________________________________ Ohio-birds mailing list, a service of the Ohio Ornithological Society. Our thanks to Miami University for hosting this mailing list. Additional discussions can be found in our forums, at www.ohiobirds.org/forum/. You can join or leave the list, or change your options, at: http://listserv.muohio.edu/scripts/wa.exe?LIST=OHIO-BIRDS Send questions or comments about the list to: [log in to unmask]