Other providers (IMAP and SMTP)

Most mailboxes outside Google and Microsoft connect over IMAP and SMTP: opendesk reads new mail from the IMAP server and sends replies through the SMTP server, so they come from your address and land in your Sent folder. You type the address, opendesk finds the servers, and you paste a password.

• App password, for providers that only accept one from mail apps: Yahoo, AOL, iCloud, Fastmail and Yandex. The wizard shows where to make it.
• Email password, for hosts that accept the mailbox’s own password, such as a hosting provider or your company’s mail server.
• Other IMAP and SMTP, to type or change the server settings yourself.

1. Create an app password: three short steps for your provider, and a button that opens the right page.
2. App password: paste it here.
3. Server settings, set for you: the provider’s IMAP and SMTP servers, ports and security. Edit switches to Other IMAP and SMTP with them filled in.

Connect with an app password or a password

1. Add the mailbox and type the address

   In Settings, open Mailboxes and click Add mailbox. Type a name and the address. opendesk shows the provider and selects App password or Email password, whichever it takes. Click Continue.

2. Create the app password

   For an app password, follow the three steps in the wizard, or see App passwords by provider below. Name it opendesk so you can find it later.

3. Paste it and connect

   Paste the app password, or the mailbox’s password, and click Connect. opendesk signs in to both servers before it saves anything, and the last step shows Receiving works and Sending works. If a server refuses, the wizard says why and how to fix it.

Providers

Provider	Way in	Where to make an app password	IMAP	SMTP
Yahoo Mail	App password	login.yahoo.com/account/security	imap.mail.yahoo.com:993 TLS	smtp.mail.yahoo.com:465 TLS
AOL Mail	App password	login.aol.com/account/security	imap.aol.com:993 TLS	smtp.aol.com:465 TLS
iCloud Mail	App-specific password, with two-factor authentication on	account.apple.com	imap.mail.me.com:993 TLS	smtp.mail.me.com:587 STARTTLS
Fastmail	App password	app.fastmail.com	imap.fastmail.com:993 TLS	smtp.fastmail.com:465 TLS
Zoho Mail	Email password, or an app password with two-factor authentication on	accounts.zoho.com	imap.zoho.com:993 TLS	smtp.zoho.com:465 TLS
Yandex Mail	App password	id.yandex.com/security/app-passwords	imap.yandex.com:993 TLS	smtp.yandex.com:465 TLS
GoDaddy, Namecheap, IONOS, Hostinger, OVHcloud, Migadu, Purelymail, Rackspace, GMX	Email password		Detected	Detected
Proton Mail	Forwarding only (see Proton Mail)
Any other host	Email password, with detected or typed settings		Detected when the domain publishes it	Detected when the domain publishes it

Zoho uses regional servers for accounts outside the US, such as imap.zoho.eu and smtp.zoho.eu. opendesk picks the right ones from the address and its MX records. For Gmail and Google Workspace, see Gmail and Google Workspace; for Outlook.com and Microsoft 365, see Microsoft 365 and Outlook.

App passwords by provider

Yahoo Mail

1. Sign in to Yahoo and open Account security.
2. Choose Generate app password, name it opendesk and choose Generate password.
3. Copy the password and paste it in opendesk.

AOL Mail

1. Sign in to AOL and open Account security.
2. Choose Generate app password, name it opendesk and choose Generate password.
3. Copy the password and paste it in opendesk.

iCloud Mail

1. Sign in at account.apple.com and open Sign-In and Security. Two-factor authentication must be on.
2. Choose App-Specific Passwords and add one named opendesk.
3. Copy the password and paste it in opendesk. Use your iCloud address, not an alias.

Fastmail

1. In Fastmail, open Settings, Privacy and Security, then Manage app passwords.
2. Create one named opendesk with access to IMAP and SMTP.
3. Copy the password and paste it in opendesk.

Zoho Mail, when two-factor authentication is on

1. In Zoho Accounts, open Security, then App Passwords.
2. Generate one named opendesk.
3. Copy it and paste it in opendesk. Also check that IMAP access is on in Zoho Mail settings, under Mail Accounts.

Yandex Mail

1. Open Yandex ID, then Security and App passwords.
2. Create a password for Mail named opendesk.
3. Copy it and paste it in opendesk. Also allow IMAP in Yandex Mail settings, under Email clients.

Settings found for you

For an address opendesk doesn’t know by name, it looks the servers up from the domain, in this order:

1. The MX records, which name hosts like Google Workspace, Microsoft 365 or Zoho.
2. The domain’s own autoconfig file, at autoconfig.<domain> or <domain>/.well-known/autoconfig.
3. Thunderbird’s provider database, when your instance has it on (it is on for opendesk Cloud).
4. The domain’s DNS service records (SRV) for IMAP and mail submission.

Only servers that offer TLS or STARTTLS are used. When the servers are found, the wizard suggests the password the host takes, usually Email password, and fills in the settings.

When nothing is found, the wizard says so: type the settings under Other IMAP and SMTP, from your host’s help pages, or forward the mail.

Other IMAP and SMTP

Other IMAP and SMTP shows every setting, filled in from what was found. Use it for your own mail server, or to change a detected setting.

1. Incoming mail (IMAP): the server, port, security, and the username (usually the full address) and password.
2. Outgoing mail (SMTP): the server, port and security. It uses the same username and password as IMAP unless you untick that and enter others.
3. Connect and test signs in to both servers, then saves the mailbox.

Ports and security

Server	Port	Security
IMAP	993	TLS
IMAP	143	STARTTLS
SMTP	465	TLS
SMTP	587	STARTTLS

Choosing a security setting fills in its usual port. If your host documents another port, type it in.

Warning

Security None sends your password unencrypted. Use it only on a private network, never over the internet.

When port 465 does not answer

Some networks block port 465. When SMTP on 465 does not answer and the same server works on port 587 with STARTTLS, opendesk uses 587 and keeps it for the mailbox. This happens when you connect and whenever you test the connection, so you don’t need to change it yourself.

If the server refuses

Nothing is saved when a server refuses. The wizard shows the cause and the fix, with the server’s own reply underneath.

What you see	What to do
Yahoo needs an app password, and the same for AOL, iCloud, Fastmail and Yandex	Create an app password as above and use it instead of the account password.
Zoho refused the password	With two-factor authentication on, use an app password. Check that IMAP access is on in Zoho Mail.
The server refused the sign-in	Check the username, usually the full address, and the password. Some hosts need an app password, or a username other than the address.
IMAP is turned off for this mailbox	Turn IMAP on in the provider’s mail settings, or ask your email admin.
The server name does not exist	Check the spelling of the IMAP and SMTP server.
The server could not be reached	Check the server and port, and that the server accepts connections from the internet.
The mail port did not answer	Use port 587 with STARTTLS instead of 465 or 25.
The secure connection failed	Match the security to the port: 465 and 993 use TLS, 587 and 143 use STARTTLS. Check that the server name matches its certificate.
Encryption is required	Use TLS on 465 or 993, or STARTTLS on 587 or 143.
The server does not take a password here	Use the provider’s submission server, usually on port 587 or 465, not the MX server or port 25.
The server must be a public address	opendesk connects only to mail servers on the public internet. Use the provider’s public server name.
Too many sign-in attempts	Wait 15 to 60 minutes before you try again.

Proton Mail

Proton Mail offers IMAP only through Proton Mail Bridge, an app on your own computer that opendesk can’t reach. Connect a Proton address by forwarding its mail instead. Forwarding is available on Proton’s paid plans.

Forwarding with SMTP

You can also bring mail in by forwarding and send replies through your SMTP server. Choose Forward mail to opendesk, then Through your SMTP server. opendesk then sends from your address without reading the mailbox.

Security

• Passwords and app passwords are encrypted at rest with AES-GCM and are never shown again after you save them.
• opendesk connects only to mail servers on the public internet.
• To revoke access, delete the app password at your provider, or change the mailbox’s password.

Related

• Connect a mailbox
• Gmail and Google Workspace
• Forwarding