SETUP GUIDEEmail · SMTP & API

Connect your email.
In about five minutes.

Campaigns send from your address, not ours, so the mail arrives from a domain your prospects recognise. Find your provider below for the exact settings and the click path to the credential you need to paste.

Three ways to connect

Your own mailbox

SMTP with your address and an app password. Replies come back to you, and Rechlio can read them. Best for most people starting out.

A sending service

SendGrid, Amazon SES or Mailgun via SMTP. Higher volume and better deliverability at scale, but no inbox behind it.

A verified domain

Add DNS records once and send through the platform. No password to manage and no per-mailbox limits.

Why it asks for an app password

Nearly every provider now refuses your normal login password over SMTP. Instead you generate a separate password that works for one application and nothing else, which you can revoke on its own without changing the password you sign in with. That is the thing to paste into Rechlio.

Almost all of them require two-factor authentication on the account first — the app password screen does not appear until you turn it on. If you cannot find the option, that is usually why.

Whatever you paste is encrypted before it is stored, and it is never shown back to you afterwards; the form displays dots and keeps what it already has unless you type something new.

Find your provider

Choosing your provider in the connect form fills the host, port and encryption for you. These are the same values, so you can check what it filled in.

Your own mailbox

Gmail / Google Workspace

Replies are read
Hostsmtp.gmail.com
Port465
EncryptionSSL/TLS
UsernameYour full Gmail or Workspace address
PasswordA 16-character app password, not your Google password
  1. 1Open your Google Account and go to Security.
  2. 2Turn on 2-Step Verification. The App Passwords page does not appear until you do.
  3. 3Go to myaccount.google.com/apppasswords, type a name like Rechlio, and select Create.
  4. 4Copy the 16 characters. Spaces in the displayed value are for readability — they are ignored either way.
  5. 5For Google Workspace, an administrator may need to allow app passwords in the Admin console under Security, then Less secure apps and app passwords.

Gmail applies a sending limit of roughly 500 recipients a day on personal accounts and 2,000 on Workspace. Campaigns above that will start failing partway through, from Google rather than from Rechlio.

Gmail / Google Workspace documentation

Zoho Mail (Workplace / Paid)

Replies are read
Hostsmtppro.zoho.in
Port465
EncryptionSSL/TLS
UsernameYour full Zoho address, e.g. you@yourcompany.com
PasswordAn app password, not your Zoho login password
  1. 1Sign in at accounts.zoho.in and open Security.
  2. 2Turn on Multi-Factor Authentication if it is not already on — app passwords do not exist without it.
  3. 3Open App Passwords, choose Generate New Password, and name it Rechlio.
  4. 4Copy the password that appears. It is shown once.
  5. 5In Zoho Mail, open Settings, then Mail Accounts, and confirm IMAP Access is enabled — this is what lets replies be read.
Zoho Mail (Workplace / Paid) documentation

Zoho Mail (Free / Personal)

Replies are read
Hostsmtp.zoho.in
Port465
EncryptionSSL/TLS
UsernameYour full Zoho address
PasswordAn app password from Zoho Security
  1. 1Sign in at accounts.zoho.in and open Security.
  2. 2Turn on Multi-Factor Authentication, then open App Passwords and generate one.
  3. 3In Zoho Mail, go to Settings, then Mail Accounts, and enable both IMAP Access and SMTP.
  4. 4Use smtp.zoho.in, not smtppro — the pro host rejects free accounts.
Zoho Mail (Free / Personal) documentation

Zoho Mail (US / .com region)

Replies are read
Hostsmtp.zoho.com
Port465
EncryptionSSL/TLS
UsernameYour full Zoho address
PasswordAn app password from Zoho Security
  1. 1Sign in at accounts.zoho.com — the .com console, not .in.
  2. 2Open Security, enable Multi-Factor Authentication, then generate an App Password.
  3. 3If you are on a paid Workplace plan, change the host to smtppro.zoho.com.

Zoho runs separate data centres. An account created in the US will not authenticate against the .in hosts and vice versa. If the password is right and login still fails, you are on the wrong region.

Zoho Mail (US / .com region) documentation

Yahoo Mail

Replies are read
Hostsmtp.mail.yahoo.com
Port465
EncryptionSSL/TLS
UsernameYour full Yahoo address
PasswordAn app password generated for "Other App"
  1. 1Open login.yahoo.com/account/security.
  2. 2Turn on 2-Step Verification.
  3. 3Select Generate app password, choose Other App, and name it Rechlio.
  4. 4Copy the password shown.
Yahoo Mail documentation

Microsoft 365 / Outlook

Replies cannot be read
Hostsmtp.office365.com
Port587
EncryptionSTARTTLS
UsernameYour full Microsoft 365 address
PasswordAn app password, once an admin has enabled SMTP AUTH on the mailbox
  1. 1An administrator opens the Microsoft 365 admin centre, finds the user, and enables Authenticated SMTP on that mailbox.
  2. 2Turn on multi-factor authentication for the account at mysignins.microsoft.com/security-info.
  3. 3Create an app password from the same page, under Add sign-in method.
  4. 4Use port 587 with STARTTLS. Port 465 is not offered.

Two dated limits, both from Microsoft. Replies cannot be read at all — basic authentication on IMAP is already switched off permanently across Exchange Online and nobody, including Microsoft support, can re-enable it. And sending is on a clock: from the end of December 2026, basic auth for SMTP AUTH is disabled by default on existing tenants and unavailable on new ones. If you are choosing a provider today, choose a different one.

Microsoft 365 / Outlook documentation

Outlook.com / Hotmail (Personal)

Replies cannot be read
Hostsmtp-mail.outlook.com
Port587
EncryptionSTARTTLS
UsernameYour full @outlook.com, @hotmail.com or @live.com address
PasswordAn app password from Microsoft account security
  1. 1Open account.microsoft.com/security and turn on two-step verification.
  2. 2Create an app password under Advanced security options.
  3. 3Use port 587 with STARTTLS.

Microsoft has been progressively closing basic authentication on personal accounts for third-party apps, and app passwords are basic authentication. This may already have stopped working on your account. Replies cannot be read.

Outlook.com / Hotmail (Personal) documentation

Hosting providers

Hostinger

Replies are read
Hostsmtp.hostinger.com
Port465
EncryptionSSL/TLS
UsernameYour full email address
PasswordThe mailbox password you set in hPanel
  1. 1Open hPanel, then Emails, and select your domain.
  2. 2Find the mailbox and use its password, or set a new one.
  3. 3Use port 465 with SSL.
Hostinger documentation

GoDaddy (Workspace Email)

Replies are read
Hostsmtpout.secureserver.net
Port465
EncryptionSSL/TLS
UsernameYour full GoDaddy email address
PasswordYour mailbox password
  1. 1Sign in to your GoDaddy Email & Office dashboard.
  2. 2Confirm the mailbox is active and note its password.
  3. 3Use smtpout.secureserver.net on port 465 with SSL.

GoDaddy applies low hourly send limits on Workspace Email. Large campaigns will be throttled by the provider.

GoDaddy (Workspace Email) documentation

Namecheap (Private Email)

Replies are read
Hostmail.privateemail.com
Port465
EncryptionSSL/TLS
UsernameYour full Private Email address
PasswordYour mailbox password
  1. 1Open the Namecheap Private Email dashboard.
  2. 2Confirm the mailbox exists and note its password.
  3. 3Use mail.privateemail.com on port 465 with SSL.
Namecheap (Private Email) documentation

Bulk sending services

SendGrid (Twilio)

Send-only, no inbox
Hostsmtp.sendgrid.net
Port587
EncryptionSTARTTLS
UsernameThe literal word apikey — not your email address
PasswordA SendGrid API key with Mail Send permission
  1. 1Open Settings, then API Keys, in the SendGrid dashboard.
  2. 2Create an API Key with Restricted Access and enable Mail Send.
  3. 3Copy the key. It is shown once and starts with SG.
  4. 4Verify your sending domain under Settings, then Sender Authentication, before sending anything real.
  5. 5Put the word apikey in the username field, exactly that, and the key in the password field.

SendGrid is a send-only relay. There is no mailbox behind it, so replies cannot be read and a sequence will not stop when somebody answers. Set a Reply-To address on a mailbox you can also connect if you need that.

SendGrid (Twilio) documentation

Amazon SES

Send-only, no inbox
Hostemail-smtp.ap-south-1.amazonaws.com
Port587
EncryptionSTARTTLS
UsernameAn SES SMTP username, which is not your AWS access key ID
PasswordThe matching SES SMTP password
  1. 1Open the Amazon SES console and pick the region you send from.
  2. 2Go to SMTP settings, then Create SMTP credentials. This creates an IAM user and derives an SMTP password from it.
  3. 3Download the credentials CSV. The password cannot be shown again.
  4. 4Change the host to match your region — the default here is Mumbai, ap-south-1.
  5. 5Move out of the SES sandbox before sending to addresses you have not verified.

Your AWS access key and secret will not work here. SES derives a separate SMTP password, and pasting the IAM secret is the single most common SES setup failure. SES is also send-only: no inbox, so no reply detection.

Amazon SES documentation

Mailgun

Send-only, no inbox
Hostsmtp.mailgun.org
Port587
EncryptionSTARTTLS
UsernameYour Mailgun SMTP login, e.g. postmaster@mg.yourdomain.com
PasswordThe SMTP password for that domain
  1. 1Open Sending, then Domains, and select your domain.
  2. 2Open SMTP credentials and copy the login, or create a new one.
  3. 3Reset the password if you do not have it — it is not shown again after creation.
  4. 4Complete DNS verification for the domain first, or Mailgun will accept the connection and refuse the mail.

Send-only. No inbox, so replies cannot be read.

Mailgun documentation

Not listed here

Any provider that offers SMTP will work. Ask them, or search their help centre, for four things: the SMTP host, the port, whether it uses SSL or STARTTLS, and whether you sign in with your email address or a separate username. Port 465 almost always means SSL and port 587 almost always means STARTTLS. Enter them under the manual option in the connect form.

Reading replies

Sending and receiving are separate capabilities, and it is worth knowing which you are getting. Rechlio watches your mailbox for answers, and an answer is what stops a sequence — so on a provider it cannot read, somebody who replies on day two still receives the day-six message.

ProviderRepliesWhat that means
Zoho Mail (Workplace / Paid)Replies are readRechlio connects to the mailbox and notices answers, so sequences stop when somebody replies.
Zoho Mail (Free / Personal)Replies are readRechlio connects to the mailbox and notices answers, so sequences stop when somebody replies.
Zoho Mail (US / .com region)Replies are readRechlio connects to the mailbox and notices answers, so sequences stop when somebody replies.
Gmail / Google WorkspaceReplies are readRechlio connects to the mailbox and notices answers, so sequences stop when somebody replies.
Microsoft 365 / OutlookReplies cannot be readThe mailbox exists, but the provider no longer allows a password to read it. Sequences will keep sending after somebody answers.
Outlook.com / Hotmail (Personal)Replies cannot be readThe mailbox exists, but the provider no longer allows a password to read it. Sequences will keep sending after somebody answers.
Yahoo MailReplies are readRechlio connects to the mailbox and notices answers, so sequences stop when somebody replies.
SendGrid (Twilio)Send-only, no inboxA relay with no mailbox behind it. Nothing can be read back, so sequences will keep sending after somebody answers.
Amazon SESSend-only, no inboxA relay with no mailbox behind it. Nothing can be read back, so sequences will keep sending after somebody answers.
MailgunSend-only, no inboxA relay with no mailbox behind it. Nothing can be read back, so sequences will keep sending after somebody answers.
HostingerReplies are readRechlio connects to the mailbox and notices answers, so sequences stop when somebody replies.
GoDaddy (Workspace Email)Replies are readRechlio connects to the mailbox and notices answers, so sequences stop when somebody replies.
Namecheap (Private Email)Replies are readRechlio connects to the mailbox and notices answers, so sequences stop when somebody replies.

If you send through a service with no inbox, you can still receive answers by setting a Reply-To address on a mailbox you connect separately. Replies land there and can be read from there.

When it will not connect

Invalid login / 535 authentication failed

Almost always the normal account password rather than an app password. Generate an app password and paste that. On Zoho, also check you are on the right regional host: an account created in the US will not authenticate against the .in hosts.

Connection timed out

Usually the wrong port for the encryption. Port 465 needs SSL and port 587 needs STARTTLS; swapping them produces a hang rather than a clear refusal.

SMTP AUTH is disabled for the mailbox

Microsoft 365 only. An administrator has to enable Authenticated SMTP on that specific mailbox in the admin centre. It is off by default on newer tenants.

Mail sends, but replies never appear

Check the table above. Either the provider has no inbox, or it no longer allows a password to read one. Neither is something a different password will fix.

The first few send, then everything fails

A provider sending limit, not a Rechlio one. Personal mailboxes cap at a few hundred a day. If you are sending more than that, move to a domain or a sending service.

Mail is accepted but lands in spam

Your domain is missing SPF and DKIM records. Add them at your DNS provider before running a real campaign — nothing about the connection settings changes this.

The connect form has a test button that sends one real message to an address you choose. Use it before launching a campaign — it is the only check that proves the whole path, credentials through to delivery.

Ready to connect

Have your app password to hand — most providers show it once and never again.

Connect your email