yeah okay, so I am wrong. i was thinking of the spams i get from @hotmail.com that dont even seem to exist. 8/13/02 3:45:07 PM, Keith Moore <moore@cs.utk.edu> wrote: >> majority of spam emails are using forged addressing, propose that receiver smtp >> server connect to the sending server and see if the server bounces on that users >> address. > >I'm doing this now for one user community, with mixed results. In particular, >I'm surprised at the number of users whose email addresses are valid (in that >if you send them mail, it will get there eventually), but for whom attempts >to validate their addresses via SMTP fairly consistently fail for temporary >reasons (e.g. DNS timeout, SMTP doesn't respond, SMTP returns 4xx). > >Keith >