Hi Guys, I've installed Mail Security 4.3.1 on our Exchange 2010 Windows 2008 R2 Server. For the past couple of days i've been making configuration changes and noting the effects. It appears that when Greylisting is activated it does a fine job of rejecting all of the spam mails that are never resent once bounced. However, there are a number of emails that are resent, passing through the greylisting filter, then apparently not being filtered by anything else. I've tried adding domains to the global blacklist but it appears that if they pass the greylisting, they are considered quality emails and the blacklist is bypassed. These are not your typical viagra emails, more spammy mailing lists that send out emails for legitimate products and services and the emails are resent if they bounce once. It seems that the alternative is to disable greylisting (which would be a shame, as it does do a great job) then use the blacklists - surely it shouldnt be a case of using one or the other? Is the above behavior by design? Or should emails be checked by the other filters once they have passed through greylisting? Any ideas greatly appreciated!