Email is the workhorse of cold outreach, and it has the strictest deliverability rules of any channel. BrandJet AI handles the sending, the throttling, and the warmup for you, but you do need to connect at least one mailbox before you can run an email campaign.
This article covers the three connection paths: Gmail and Google Workspace by OAuth, Outlook and Microsoft 365 by OAuth, and any provider by SMTP and IMAP. It also covers bulk import and the most common reconnection errors.
Before you start
Pick the right path for your mailbox.
If your email is on Gmail or Google Workspace, use the Google OAuth flow. It is the most reliable and survives password changes.
If your email is on Outlook or Microsoft 365, use the Microsoft OAuth flow.
If your email is on a cold email infrastructure provider like Mailforge, Inboxing, ScaledMail, Winnr, Postal, Hostinger, GoDaddy, or anything else that gives you SMTP credentials, use SMTP and IMAP. This is also the right path for any mailbox where OAuth is blocked by your admin.
If you have not bought a domain yet and you want to send cold email, do that first. See Set up a sending domain and email warmup. Sending cold from your real company domain is a fast way to damage its reputation.
Connect Gmail or Google Workspace
The Google OAuth flow takes about a minute.
From the sidebar, click Accounts, then click Add account, then pick Email, then pick Google.
You are redirected to Google. Sign in with the mailbox you want to connect. If you have multiple Google accounts, pick the right one carefully. The mailbox you sign in with is the mailbox that gets connected.
Google shows the permissions screen. The first time you connect a Gmail account, you may see a screen that says the app is unverified. Click Continue. BrandJet AI is a Google verified application, and the warning sometimes shows up when the workspace admin has restricted the trust list. If the admin has fully blocked third party apps, you will need them to allow BrandJet AI before you can continue.
After you approve, you are redirected back to BrandJet AI. The account shows up under Accounts in Pending status for about thirty seconds, then flips to Active.
If you see an error after redirect, the most common cause is that your Google Workspace admin has blocked external OAuth apps. Ask your admin to allow BrandJet AI in the Google Admin console under Security, then API Controls, then App access control. Once the app is allowed, retry the connection.
Connect Outlook or Microsoft 365
The Microsoft OAuth flow is similar but has one extra step for some tenants.
From the sidebar, click Accounts, then click Add account, then pick Email, then pick Microsoft.
You are redirected to Microsoft. Sign in with the mailbox you want to connect.
Approve the permissions BrandJet AI requests.
You are redirected back to BrandJet AI. The account shows up under Accounts in Pending status, then flips to Active.
If your tenant has multifactor authentication required, you may need to approve the connection from your Microsoft Authenticator app on top of signing in. If you see an MFA error, complete the prompt on your phone and try the connection again.
If your tenant blocks third party apps entirely, your admin needs to allow BrandJet AI in Entra ID under Enterprise applications. Once that is done, the connection will go through.
Connect by SMTP and IMAP
Use this path for any provider that does not support OAuth, or when your admin has blocked the OAuth flow. This is also the path that cold email infrastructure providers like Mailforge, Inboxing, ScaledMail, Winnr, and Postal tell you to use.
You will need four pieces of information from your provider:
SMTP host and port (used for sending). Common values are something like smtp.mailforge.ai on port 587 or 465.
IMAP host and port (used to read replies). Common values are something like imap.mailforge.ai on port 993.
The mailbox username, which is usually the full email address.
The mailbox password, or an app specific password if your provider requires one.
To connect:
From the sidebar, click Accounts, then click Add account, then pick Email, then pick SMTP.
Paste in the email address, password, SMTP host, SMTP port, IMAP host, and IMAP port.
Click Test connection. BrandJet AI sends a test message through SMTP and pulls one message through IMAP to verify both directions work.
If the test passes, click Save. The account moves to Active.
If the test fails, the error message tells you which side broke. The most common causes are a wrong port (SMTP is usually 587 or 465, IMAP is usually 993), a typo in the password, or your provider requiring an app password rather than your account password. For Gmail and Outlook, do not use SMTP unless your admin has blocked OAuth. The OAuth flow is always more reliable.
Bulk import many mailboxes at once
If you have ten or twenty SMTP mailboxes to connect, do not enter them one by one.
From the Accounts screen, click Add account, then pick Email, then pick SMTP, then click the Bulk import tab.
Download the CSV template. The columns are email, password, smtp_host, smtp_port, imap_host, imap_port.
Fill in one row per mailbox.
Upload the CSV. BrandJet AI tests each mailbox in parallel and shows you which ones passed and which ones failed.
Bulk import is currently only available for SMTP. For Gmail and Outlook, each mailbox has to go through OAuth individually, because Google and Microsoft do not allow bulk OAuth grants.
Set your sending limits
After an account is Active, click it and open Sending settings. The defaults are conservative: forty emails per day, five per hour. We recommend leaving these alone for the first few weeks while the mailbox warms up. Once warmup completes, you can raise the daily limit gradually. The Set up a sending domain and email warmup article walks through this in detail.
The From name on the account also lives in Sending settings. If your campaigns are signing your full company name and you want them signed with just your first name, change the From name here.
Common errors
Invalid credentials. The password was wrong, or the provider has revoked the session. Reconnect using the Reconnect button on the account card.
Configure new app option missing. Some Gmail screens hide the Configure new app menu when you are signed in as a regular user. Sign in to admin.google.com with a workspace admin account, then come back to the connection flow.
App is trusted, but error on redirect. Your workspace admin has flagged BrandJet AI as trusted but has not yet allowed the scopes. Ask the admin to allow the requested scopes in the same Trust screen.
MFA required. Approve the prompt on your phone and try again.
CRLF or RFC2821 errors with Postal. This is rare and shows up only with self hosted Postal servers. Contact support and include the server logs from your Postal instance.
What to do next
Once you have at least one email account connected, go to Set up a sending domain and email warmup to get the mailbox ready to send safely. After that, work through Upload or find your leads and then Create a multichannel campaign.