--- title: "How to Connect a Mailbox in FirstSales | FirstSales" description: "Connect a sending mailbox via Google, Microsoft, or SMTP/IMAP, authenticate the domain, and turn on warm-up before your first send." canonical: "https://firstsales.io/tutorial/connect-mailbox/" --- [Home](/)/[Tutorials](/tutorial/)/How to Connect a Mailbox in FirstSales Mailboxes # How to Connect a Mailbox in FirstSales Connect a sending mailbox via Google, Microsoft, or SMTP/IMAP, authenticate the domain, and turn on warm-up before your first send. 7 min read·Beginner·6 steps 1. 1 ## Open Connectors and click Add Connector In FirstSales a sending mailbox is called a **connector** — "the mailboxes and integrations that send your campaigns." Open the **Connectors** page from the left nav and click **Add Connector** (top-right). Every campaign sends _from_ a connector, so this is the first thing to set up before launching anything. You can add as many as you like. ![Open Connectors and click Add Connector](/tutorials/warmup-01-add-connector.webp) 2. 2 ## Pick how you'll connect Choose one of three email account types: * **Google** — connect a Google Workspace account via OAuth (one click, no password stored). * **Microsoft** — connect a Microsoft/Outlook account via OAuth. * **SMTP / IMAP** — connect any other provider with server credentials. **Important:** for Google, only **Google Workspace** accounts are supported — personal `@gmail.com` addresses are not allowed. Use a domain mailbox (e.g. `you@yourcompany.com`). 3. 3 ## Connect with Google or Microsoft (OAuth) For Google or Microsoft, click the connect button and a popup opens to authorize FirstSales. Sign in and grant access; the window shows _"Waiting for authorization…"_ and then confirms **"{Provider} connected"**. FirstSales never sees or stores your password — it holds a revocable OAuth token. If your Google Workspace admin restricts third-party apps, they may need to allow FirstSales in the admin console first. If authorization fails, use **Try again**. ![Connect with Google or Microsoft (OAuth)](/tutorials/warmup-02-email-auth.webp) 4. 4 ## Or connect via SMTP / IMAP For any other provider, choose **SMTP / IMAP** and the **Single Account** tab. Fill in: * **Email address** and optional **Display name**. * **Username** and **Password**. * **Outgoing (SMTP)**: host, port (587 / 465 / 25 / 2525 or custom), encryption (TLS / SSL / None). Default 465 / SSL. * **Incoming (IMAP)**: host, port (993 / 143), encryption. Default 993 / TLS. IMAP is included so FirstSales can read replies and route them to your inbox. 5. 5 ## Test the connection, then add the account For SMTP/IMAP you must click **Test connection** first. On success you'll see _"Connection verified — ready to save,"_ and only then can you click **Add account** — you can't save an untested mailbox. A toast confirms **"Email account added!"** This test catches wrong hosts, ports, or app-password issues up front, so a bad mailbox never silently fails mid-campaign. 6. 6 ## Warm it up before sending A brand-new mailbox has no sender reputation. Before you point real campaigns at it, open the connector's **Warm Up** tab and enable warm-up so it gradually builds reputation. See the email warm-up tutorial for the full setup. Connecting the mailbox is step one; warming it is what keeps your first real sends out of spam. ![Warm it up before sending](/tutorials/warmup-03-warmup-toggle.webp) ## Pro tips Hard-won shortcuts that keep warm-up on track. 1 ### Use a Google Workspace account, not personal Gmail Personal @gmail.com addresses aren't supported — only Google Workspace (domain) accounts. Cold outreach should send from your own domain anyway, so this lines up with good practice. 2 ### OAuth beats SMTP when you have the choice Google and Microsoft OAuth store a revocable token, not your password, and reconnect cleanly if access lapses. Reach for SMTP/IMAP only when your provider isn't one of those two. 3 ### A failed test now saves a dead campaign later The SMTP 'Test connection' gate exists so a wrong port or password surfaces immediately. Don't work around it — fix the credentials until the test passes. 4 ### Connect, then warm up A freshly connected mailbox has zero reputation. Turn on warm-up right after connecting so it's ready by the time you launch real outreach. ## Frequently asked questions What is a 'connector'? It's FirstSales' name for a sending mailbox (or integration) — the account your campaigns send from. You manage them on the **Connectors** page and add one with **Add Connector**. Which mailbox types can I connect? Three: **Google** (Workspace, via OAuth), **Microsoft**/Outlook (via OAuth), and **SMTP / IMAP** for any other provider using server credentials. Can I use a personal Gmail account? No. Only **Google Workspace** accounts are supported for Google — personal `@gmail.com` addresses are blocked. Connect a mailbox on your own sending domain instead. Does FirstSales store my password? For Google and Microsoft, no — it uses **OAuth** and holds a revocable token. For SMTP/IMAP you provide credentials directly so it can send and read replies; use an app password where your provider offers one. Why do I need IMAP settings too? IMAP lets FirstSales read incoming mail so replies to your campaigns land in your FirstSales inbox and can end a contact's sequence. That's why the SMTP/IMAP form asks for both outgoing and incoming servers. Why can't I click 'Add account' yet? For SMTP/IMAP you must run **Test connection** first. Until it verifies (_'Connection verified — ready to save'_), the save button stays disabled — this prevents adding a mailbox that can't actually send. What if OAuth authorization fails? Use **Try again**. If it keeps failing on Google Workspace, your admin may need to allow FirstSales in the Google admin console. For an existing connector that lost access, use **Reconnect account** on the connector card. What should I do right after connecting? Enable **warm-up** on the connector's Warm Up tab. A new mailbox has no reputation, and warming it first is what keeps your early sends landing in the inbox. ## Ready to put this into practice? Start your FirstSales trial and launch a warmed, authenticated mailbox in minutes. [Start for $1](https://app.firstsales.io) [All tutorials](/tutorial/)