Advanced spam filter rules and spoofed email addresses

[krysia]

I'm getting a lot of spam supposedly from my own email address.  I've set up advanced filtering rules, which should send emails purportedly from my own address as well as anything with fail or none for received-SPF or certain subject headings to my junk folder.  However, the emails supposedly from me keep ending up in my inbox, even though they break all three of these advanced filter rules.  Is this because there's some kind of default rule that will not send something to junk if it seems to come from my address? I have my own domain name and DKIM and DMARC are attached to it, so there's a difference between my real address and spoofs of it.

[Simon]

Is this an IDNet email address?  I must admit to finding filtering a bit of a black art, but I've managed to get mine working to reasonable effect.  Just a shot in the dark, but have you tried the filters in a different order?

[krysia]

It's our own domain name, and the email gets forwarded automatically to our idnet.com addresses.  I have tried changing the order a bit, but it doesn't seem to make a diference.

[Simon]

So are the filters active on your own domain email server, before the emails are forwarded to your IDNet address?  If so, perhaps you could set up the same filters on your IDNet email account?  If not, then maybe the emails are getting forwarded before they're passing through the filters on your own domain?

[krysia]

I'm not that technologically advanced!  IDNet hosts our domain name and has set up DKIM and DMARC for us so mail we send is clearly legit - I've used IDNet's spam filter to weed out incoming junk.  It works fine, apart from this issue of not stopping any mail that spoofs my address, even when it has banned subject headings and/or has failed SPF or has no SPF report.

[Simon]

I would suggest, as IDNet have set this up for you, that they might be the best people to ask for help.   

[krysia]

Thanks for your help, Simon - will do!