I have a personal server with it's own control panel. This allows me to block unwanted spam at the server level direct (Not a web based email address).This works pretty well. I do receive some e mails which appear to have my email address as the sender. Obviously this is done so that one is reluctant to block ones own address. With outlook the junk mail filter works fine either with a mail with a false sender ID, or with my own address forged and does not block my mail.
I analyse the headers in junk mail to try to establish the real sender ID and this works to a fair degree and I block this in my personal control panel on my server.
However, my query is that how comes Outlook's junk mail recognise the true sender and blocks without affecting my own address? What is it seeing that I cannot always find in the mail headers? If I knew this, I could then firmly block at server level without being wary od blocking the ISP completely.