Spam classification and custom routing rules solve different problems. Spam Filters assess incoming mail, while Email Filters let you act on selected message characteristics. Global rules can affect more mailboxes than expected.
Start cautiously
- Record existing settings and choose the mailbox or domain scope.
- Prefer marking or moving suspected spam for review before enabling automatic deletion.
- Create narrowly defined rules with clear names. Avoid a broad subject match that could catch genuine customer messages.
- Use the available rule-testing facility and send harmless sample messages.
- Review the spam folder and false positives regularly, especially after changing a threshold.
Do not confuse sender text with trust
A displayed sender name can be forged. Allowing all mail that claims to come from a familiar business may let phishing through. Review authentication and attachments as well as the visible address.
If important messages disappear, inspect mailbox rules, global filters, forwarding and client-side rules. Check Track Delivery to establish whether the server received them. Keep a change record so the last rule can be reversed.
Blocking all unfamiliar senders is rarely practical for a sales inbox. Use measured filtering, staff awareness and a monitored alternative contact channel instead.
Official references
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