How Do I Change My Mailbox's IMAP and SMTP Settings?
Yes — you can change a connected mailbox's mail server, port, sign-in name or password at any time, without deleting it. Open the Mailboxes page, click the three dots (⋮) on the mailbox and choose Edit connection settings. Your warmup history, schedule and campaigns stay exactly as they are.
Step by step:
1. Go to Mailboxes and find the mailbox.
2. Click the three dots (⋮) at the end of its row and choose Edit connection settings. You can also open Mailbox Details and use the Edit connection settings button on the SMTP or IMAP tab.
3. Change what you need. The window has two sections — Outgoing mail (SMTP) and Incoming mail (IMAP) — each with its own server, port and sign-in name.
4. Only type a password if it has changed. For your safety we never show the saved password; leaving the box empty keeps it.
5. Click Test & save. We sign in once on the outgoing side and once on the incoming side using your new settings. If both work, they are saved. If either fails, nothing is changed and the window tells you which side failed and what to check.
What each setting means:
- Server — just the server name your email provider gave you, like mail.yourdomain.com. No http://, no spaces and no @.
- Port and security — the port decides how the connection is secured. Outgoing: 465 is secure from the first byte (SSL/TLS); 587 starts plain and upgrades to secure (STARTTLS). Incoming: 993 is SSL/TLS; 143 is STARTTLS. The window shows which one your port means and has one-click buttons for the usual choices.
- Sign-in name — usually your full email address. Some providers use a different name (for example, an alias that signs in through its main mailbox).
- Password — the password for that mailbox, or an App Password if your provider uses them.
Incoming mail uses IMAP. WarmySender does not use POP, so there is no POP setting to find — if your provider lists both, use the IMAP details.
Not available for Google and Microsoft sign-in mailboxes: if you connected with the Sign in with Google or Sign in with Microsoft button, there are no server details to edit. Use Reconnect from the same three-dot menu to refresh the sign-in.
If a mailbox shows a connection problem, the three-dot menu also offers Fix Credentials, which re-checks the saved settings with a new password. Edit connection settings is the one to use when the server, port or sign-in name itself has changed.
Common questions:
- Will I lose my warmup progress? No. The mailbox is changed in place, so its history, ramp and campaigns carry on.
- Why didn't it save? Both sides must connect with the new settings. Read the message under the failed side — usually a wrong server name, a port that does not match the security type, or a password that needs to be re-entered.
- Will a failed attempt pause my mailbox? No. A failed test changes nothing, so a typo cannot disrupt a mailbox that is working.
- Where do I find my provider's settings? In your email provider's help pages or webmail settings, under IMAP and SMTP. See /documentation/connecting-mailboxes-without-app-passwords for common providers.
Full explainer: /documentation/change-mailbox-imap-smtp-settings