Xfinity Connect: Email Filter Rule to Block all email but allow certain domains and addresses

[Harley555]

How do I (or can I) setup an email Filter Rule to Block all email but allow certain domains and addresses.  I would imagine it would be more than one rule in a certain order to achieve this.  In playing around I am unable to use wildcard characters in a condition to then discard all email.  Any help will be appreciated.  TIA

[Again]

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@Harley555 wrote:

How do I (or can I) setup an email Filter Rule to Block all email but allow certain domains and addresses.  I would imagine it would be more than one rule in a certain order to achieve this.  In playing around I am unable to use wildcard characters in a condition to then discard all email.  Any help will be appreciated.  TIA

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Setting up a filter[s] would be very time consuming.  What you want is the Email Safe list.  Click on the gear icon and then on Settings.  In the left pane under Advanced Settings you want to put a check mark in the box under Email Safe list.

[Harley555]

I've already tried The Safe List and it only allows full email addresses.  I would like to allow domains as well.  So I am back to filters.  There must be a way to essentially block everything, then allow listed domains and email addresses.  I would forsee a rule to block everything, then a second rule to accept list domains and email addresses.  Wildcard characters would be in play doing this I would imagine.  Can anyone help?

[Harley555]

What would help is a document that describes the different "conditions".  Some are obvious, but some I don't know what they mean.  See screen shot ....

[BruceW · Accepted solution]

The image you posted isn't visible. It looks like this:

This is probably because you are a new poster and the image requires moderator approval. That could take a while. If you don't want to wait you could upload the image to a file sharing site and post a link to it here, or post text instead of an image.

I don't see a way to do what you want, and Comcast does not appear to have anything but the most basic documentation for filter options or syntax. But . . .

https://forums.xfinity.com/t5/Email-Web-Browsing/blocking-emails-from-nl/m-p/3198983#M206812 has a little information on the Regex and Matches keywords.  A search like https://www.google.com/search?q=Open-Xchange+filter+options+syntax& may find some info, like https://oxpedia.org/wiki/index.php?title=HTTP_API_MailFilter.

[Harley555]

@BruceW

Thanks, this helps.  By chance do you know what the "greater than" sign means in the regex used in the post to block email from TLD NL?  I understand the other characters, but not ">"

Sender/From   Regex               \.nl>$

[BruceW]

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@Harley555 wrote: ... do you know what the "greater than" sign means ...

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It's a literal character. Sometimes email addresses appear in "bare" form, like 

     user@domain.tld

and sometimes they are surrounded by angle brackets like

    <user@domain.tld>

In this instance we needed to test for addresses ending in both ".nl" and ".nl>".

There is probably a more elegant way to do this, but my Regex is REAL rusty!

[Harley555]

My working solution consists of two rules in the following order:

Rule #1 "keep"(s) email from senders and domains listed as multiple Conditions "Sender / From - Contain"  It's a short list, easy to maintain under my set of circumstances and purpose.  Then stop processing rules.

Rules #2 moves ALL other email to the trash folder using a Condition "Sender / From - Regex" with a "period".

Thanks to BruceW to help be better understand Regex.