Bounce rules tell Mumara how to classify each bounced email. You manage them under Setup → Bounce Rules. Every bounce is matched against your rules in order from top to bottom — the first matching rule wins — and is classified as one of three types:
Soft bounce — a temporary failure (mailbox full, server busy, greylisting). The bounce is recorded, but the contact keeps receiving emails since the issue may resolve.
Hard bounce — a permanent failure (user unknown, invalid address, domain not found). The contact is flagged and will not receive any further emails, protecting your sender reputation.
Exclude from processing — the bounce is ignored entirely (useful for auto-replies and out-of-office messages).
Each rule has a name, a status toggle, and one or more conditions matched against the Bounce Code (e.g. 550, 5.1.1), Bounce Reason, or Bounce Description, using "Is" or "Contains" operators. Multiple conditions are combined with AND logic. Reorder rules by dragging the handle on each row — put specific rules near the top and catch-alls at the bottom. The built-in Global Rule stays fixed at the top as the default.
Mumara ships with sensible defaults: Re-Sync Default Bounce Rules updates them while keeping your custom rules, while Reset to Default Bounce Rules wipes all custom rules and cannot be undone. As a rule of thumb, 4xx codes are temporary (soft) and 5xx codes are permanent (hard).
