How can I set a filter so that traffic from a particular domain and all of the URLs under it are not counted in my traffic?
E.g. I want to exclude everything from
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Not sure why you are trying to apply a filter, but I will suggest excluding referral traffic coming from example.com instead.
This is the simplest way to accomplish what you want to do, the referral traffic generated from that domain and all the inner pages will be excluded from the reports.
For more information about referrals and how to exclude specific domains follow these instructions