Mailbox operations

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Overview

Mailboxes determine who sends sequence emails, where replies are routed, and how quickly queued emails can leave Unify. Most mailbox controls live in Settings → Deliverability → Mailboxes and organization-level sending controls live in Settings → Sequences. Some controls apply only to Unify-managed mailboxes. Connected Gmail mailboxes can have different authorization and forwarding behavior because they are tied to the connected Google account.

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Assigned user and mailbox ownership

Each mailbox has an assigned user. For Unify-managed mailboxes, the assigned user is the person represented by the mailbox:

• The sender display name and email signature come from the assigned user.
• Replies to the mailbox are forwarded to the assigned user’s primary email.
• Sequence tasks can use the assigned user, depending on the sequence’s task assignment settings.
• Plays can select the mailbox through owner-based routing.

Admins with permission to manage email integrations can change the assigned user from the mailbox details page. If the assigned-user field is disabled, contact a workspace admin. If the mailbox is managed by Unify and the change is not available in your workspace, contact Unify support or your CSM.

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Reply routing and forwarding

When a recipient replies to a sequence email, they reply to the sending mailbox address. For example, replies to jane@mybusiness.io are received by that mailbox and forwarded to the assigned user’s primary email. Unify-managed mailboxes can also have a secondary forwarding user. Secondary forwarding sends a copy of replies to another user, such as a teammate covering for the assigned user. It does not change the sender address that the recipient sees. In mailbox details, the Forwarding Email field shows the current forwarding destination when Unify can read it from the provider. If forwarding looks wrong or is missing, check the mailbox details page and the mailbox provider before changing sequence routing.

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Warmup and ramp-up

New Unify-managed mailboxes warm before they are used for normal sequence sending. During warmup, Unify sends warmup emails through a warmup network, monitors engagement, and helps build mailbox reputation. The existing mailbox configuration guide describes the standard warmup process. A mailbox can show these operational states: Mailbox ramp-up starts at 0 for new mailboxes or at the previous daily send limit for existing mailboxes. When enabled, it increases the daily send limit until it reaches the configured maximum.

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Send limits and scheduling

Unify uses send limits and schedules to protect deliverability. At the organization level, admins can set the maximum number of sends per mailbox per 24 hours. A mailbox can also override the organization limit from the mailbox details page. Unify recommends 25 emails per mailbox per day by default. Each sequence’s send schedule sets its sending windows, time zone, and skipped dates. Emails ready outside those windows wait for the next available sending time. The mailbox’s capacity is shared across the sequences that use it.

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Backlog and queued emails

Queued sequence emails wait in the outbox until the selected mailbox has send capacity during an allowed send window. A mailbox with a large backlog may have valid queued emails that are simply waiting for capacity. When a specific sequence email is delayed, check:

• The enrollment status and step status.
• The mailbox status: warm, ramping, paused, or unauthorized.
• The mailbox daily send limit and current daily send limit.
• The sequence send schedule and allowed send days.
• Whether other pending outbox messages are already using that mailbox’s daily capacity.

If volume drops unexpectedly across a workspace, compare the number of active mailboxes, their send limits, warmup/ramp-up state, paused or unauthorized mailboxes, and the number of blocked or bounce-stopped enrollments.

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Recipient eligibility and bounce safeguards

The sequence’s ruleset controls whether emails can be sent to catch-all, unverified, and role-based addresses. Unify checks the recipient before sending. Invalid addresses are always blocked. When verification prevents sending, the enrollment can end with Bounce stopped. Review the person’s email address and the sequence’s ruleset. The enrollment guide explains how to investigate other reasons outreach may stop.

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Troubleshooting