Fake mail detection fails in google,yahoo,hotmail

Question

What are the parameters used in spam detection? I mean it is possible to send an email from some fakemailserver.com server to gmail, and the mail goes directly into the inbox, I have tested it on Goole,Yahoo and Hotmail. A fake mail from xyz@yahoo.com send from a free smtp server went straight into gmail inbox.

Answer 1

Gmail, Yahoo mail & all other mail service providers use their own secret filtering algorithm. But what we can do to detect a fake mail is - 1. Read carefully the content the mail.Fake mails have suspicious contents. 2. Check for the header part of the mail, if the mail is from the domain @gmail.com then it should come from gmail server.

Answer 2

It depends on the spam filter. Factors used include the address, the source ip, the subject, the text content, the number of similar messages, the format of the content and the use of references to external HTTP resources.