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Fix a disconnected mailbox

Reconnect a Google or Microsoft mailbox when its authorization lapses, or re-test a credential mailbox. So sending never silently stops.

Tutorials
Mailboxes
min read
4 min
steps
7 · Beginner

  1. Connectors → open the mailbox

    When a campaign stops sending from an account, open it from Connectors and look at the Details tab first.

  2. Spot the expired-token alert

    For Google or Microsoft mailboxes, a disconnected token shows an amber alert with the failure reason and a prominent Reconnect Account button.

    Spot the expired-token alert

  3. Click Reconnect Account (OAuth)

    For Google or Microsoft, click Reconnect Account, re-authorize in the popup, and the mailbox is live again: no password stored.

  4. Or run Test Connection

    If there's no alert but you suspect a problem, click Test Connection. Success shows “Connection verified!” An OAuth failure is turned into reconnect guidance automatically.

  5. Check Verified / Last verified

    These fields confirm the mailbox's current auth state and when it last passed a check: a stale Last verified date is a hint to re-test.

  6. Fix credential (SMTP/IMAP) mailboxes

    Credential mailboxes have Test Connection but no OAuth reconnect. If the test fails (for example after a rotated app password) delete the connector and re-add it with fresh credentials.

  7. Re-check sending

    After reconnecting, confirm the mailbox is still selected in your campaign's senders and that its daily limit and warm-up settings are intact.

Pro tips

  • Check Connectors first when sends drop

    A disconnected mailbox is the most common cause of a campaign that stopped sending. The Details tab tells you in one glance.

  • Reconnect keeps your settings

    OAuth reconnect restores authorization without wiping the mailbox's daily limit, warm-up, or signature: you don't rebuild anything.

  • Rotated an app password? Re-test, then re-add

    Credential mailboxes can't reconnect in place; a failed test after a password change means delete and re-add with the new one.

  • Watch for the alert proactively

    The amber token alert appears the moment a test detects a lapse: don't wait for a customer to report silence.

Frequently asked questions

My campaign stopped sending from one mailbox: why?

Most often its authorization lapsed. Open the mailbox in Connectors: a Google/Microsoft token expiry shows a reconnect alert.

How do I reconnect a Google or Microsoft mailbox?

Click Reconnect Account on the Details tab and re-authorize in the popup.

Does reconnecting lose my settings?

No: daily limit, warm-up, and signature stay in place; only the authorization is refreshed.

What does Test Connection do?

It verifies the mailbox can send (and read, for IMAP); an OAuth failure is turned into reconnect guidance.

There's no Reconnect button on my SMTP/IMAP mailbox: why?

Reconnect is OAuth-only (Google/Microsoft). Credential mailboxes use Test Connection; if it fails, re-add the connector with fresh credentials.

How do I fix a mailbox after changing its app password?

Re-test it; if the test fails, delete the connector and add it again with the new password.

How do I know when a mailbox last worked?

The Last verified field shows when it last passed a connection check.

Will FirstSales alert me automatically?

The expired-token alert appears the moment a test detects a lapse; also watch the Alerts center for mailbox-down notices.

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Install with AI

Your coding agent sets up the FirstSales CLI and skills for you.

Prompt for Claude Code

I'm setting up FirstSales (https://firstsales.io), an AI outbound sales platform: campaigns, contacts, a reply inbox, deliverability and lead signals. Help me get my workspace sending real, good emails end to end, from Claude Code.

Read these first so you know how FirstSales works:
- Developer docs and API: https://developer.firstsales.io
- CLI: https://www.npmjs.com/package/@firstsales.io/cli
- Skills for coding agents: https://github.com/firstsalesio/firstsales-skills (read README.md and GUIDE.md)

Setup
1. Install the CLI: npm install -g @firstsales.io/cli
2. Install the FirstSales skills:
   claude plugin marketplace add firstsalesio/firstsales-skills
   claude plugin install firstsales@firstsales
3. Ask me if I already have a FirstSales account. If not, send me to https://app.firstsales.io to sign up.
4. Ask me to create an API key under Settings → API → API Keys, with only the scopes we need.
   Never ask me to paste the key into this chat. Tell me to run this in my own terminal, so the key stays hidden:
   read -rs FS_KEY && firstsales auth login --api-key "$FS_KEY"; unset FS_KEY
5. Run `firstsales whoami` and tell me which workspace and organisation we are connected to.

Then ask me about my business: what I sell, who I sell to (roles, company size, countries), my best customers, and what I use today for outbound (tools, lists, mailboxes). Walk me through:
1. Teaching FirstSales my business: website, offer, proof points and case studies in the knowledge base, so the AI writes like someone who knows the product.
2. Connecting my sending mailboxes and checking my sending domain: SPF, DKIM, DMARC and warm-up. If anything is unhealthy, tell me the exact DNS record to add.
3. Bringing in contacts: import my CSV or CRM export into a clean list, remove duplicates and bad emails, and block domains I must never email (customers, competitors, my own).
4. Building my first campaign: the right list, senders, steps and timing. Write the sequence with me, show me the drafts, and do not launch until I say yes.
5. Setting up Signals if it fits: find people engaging with LinkedIn posts about topics my buyers care about, and turn them into leads.
6. Inviting my team and giving each person the right access.

Once campaigns run, show me how to work the reply inbox from here: which replies need an answer, draft responses in my voice, and move good conversations into deals. If I use Cal.com, connect it so follow-ups can offer my booking link (not the first email).

Throughout, as you learn about my business, proactively suggest and help create:
- Reply templates for the questions and objections my prospects are likely to raise, based on my product, site and codebase if you can see them.
- Campaign ideas and segments worth testing, with the reason for each.

Safety rules:
- Show every change as a dry run (--dry-run) first and wait for my yes. Never send emails, launch campaigns or delete anything without my yes.
- Tell me before anything that spends credits, and how many.

Be opinionated. If the docs give a sensible default, just use it. Don't make me choose between five options.
Developer docs ↗npm: @firstsales.io/cli ↗GitHub: firstsales-skills ↗