"Has not been previously delivered" & "Stop Processing Rules" - help wanted

[chrisisbd]

This relates to my recent previous question about the order in which cPanel processes E-Mail forwarding and filtering rules.

What do "Has not been previously delivered" & "Stop Processing Rules" really do?

I have a set of filtering rules which use the "Redirect to E-Mail" action to send a user's E-Mail to an address which is outside the domain handled by cPanel. Thus if an incoming mail is addressed to fred@this.cpanelsystem.com there's a filter rule that matches on "Recipient contains fred" and sends the mail off to fred@anothersystem.com using "Redirect to E-Mail".

So there's no mailbox on the cPanel system for fred and there needn't actually be any maiboxes at all except the system account one. If no filtering rule matches an incoming E-Mail where does it go? Presumably the default set up will send an error back to the sender via the "Discard with error to sender (at SMTP time)" which is the default way to handle it and the mail will be discarded.

But then how does "Has not been previously delivered" act, is it meaningless for my case as the mail never gets delivered or does the filtering "Redirect to E-Mail" count as a delivery? In this context is there *any* difference between a forwarding rule and a filter rule which says "Any recipient equals fred@this.cpanelsystem.com"?

... and does "Stop Processing Rules" stop *all* further processing and discard the message? If not where does the message go in the above case where there's no mailbox for it? Or does "Stop Processing Rules" just mean stop processing *these* rules but go on to (say) forwarding and/or user filtering?

It's all very ill-defined and I wish there was some proper documentation that would tell how all these bits interact with each other.

[Infopro]

Thus if an incoming mail is addressed to fred@this.cpanelsystem.com

Why would someone be sending fred and email at this address? fred@hisdomain.com sure, but not to the hostname. That isn't an email address.

[chrisisbd]

Why would someone be sending fred and email at this address? fred@hisdomain.com sure, but not to the hostname. That isn't an email address ".

?? What do you mean "That isn't an email address"? I do *exactly* this already, all mail for one user in particular is routed to an E-Mail address on another system on a domain quite separate from the domain where cPanel is running. (It's me actually, I get all my mail delivered to my home server system which runs an SMTP server and the mail ends up in a Unix style mail spool on the local file system from where I read locally)

So while most mail to the cPanel domain *is* delivered to POP3/IMAP mailboxes on the cPanel domain some is routed off to another domain. I.e., as I was trying to clarify in the example, mail for fred@this.cpanelsystem.com is forwarded to fred@anothersystem.com where anothersystem.com happens (in my case) to be my home system whose nameservers, zone file, etc. are maintained on systems completely unconnected with the cPanel hosting system I use.