Who This Is For / When to Use
Account admins configuring outbound email delivery
Users who want to send emails from Kyrios using their own email provider instead of the Kyrios default
Businesses that need SMTP-based sending for workflows, campaigns, or transactional emails
What Is SMTP in Kyrios
SMTP (Simple Mail Transfer Protocol) is the outbound email method Kyrios uses to send emails on your behalf.
Connecting an SMTP provider allows Kyrios to send emails using your email address and provider credentials.
Important: Kyrios Systems is the recommended provider because it reports full email analytics back into the platform. Third-party SMTP providers may not.
How to Add a 3rd-Party SMTP Service
Step 1: Navigate to Email Services
Go to Settings.
Select Email Services.
Confirm you are on the SMTP Service tab.
Step 2: Add a New SMTP Service
Click + Add Service in the top-right corner.
Step 3: Choose “Other” as the Provider
In the SMTP Provider dropdown, select Other.
This option is used for Gmail, Outlook, Yahoo, and most custom SMTP providers.
Step 4: Complete SMTP Configuration Fields
Fill out all required fields in the popup:
Provider Name
A label for internal reference (example: “Gmail SMTP” or “Outlook SMTP”).SMTP Server
The outbound SMTP server address (example:smtp.gmail.com).SMTP Port Number
Common ports include:587(TLS – recommended)465(SSL)
Username
Usually the full email address.Email
The sending email address.Password
Your email password or app-specific password (recommended for Gmail and Outlook).
Use outbound SMTP details only (not IMAP or POP).
Step 5: Find the Correct SMTP Server and Port
If you are unsure which SMTP server or port to use, reference the outbound SMTP details for your provider here:
https://www.arclab.com/en/kb/email/list-of-smtp-and-imap-servers-mailserver-list.html
Step 6: Save the SMTP Service
Click Save.
Watch your inbox for any verification or security confirmation emails.
Approve or confirm the connection if prompted.
Common Issues and Fixes
Emails Fail to Send After Setup
Cause: Provider verification email not approved.
Fix: Check your inbox and confirm any security or login alerts from your email provider.
Emails Go to Spam or Are Blocked
Common Causes:
SMTP email does not match the email used in workflows.
Provider reputation or daily sending limits.
Missing SPF/DKIM authentication.
Fixes:
Always use the same email address in:
SMTP setup
Workflows and campaigns
Avoid switching sender addresses across providers.
Consider a dedicated sending domain or Mailgun for scale.
Gmail, Outlook, or Yahoo Delivery Issues
If you use Gmail, Outlook, or Yahoo as your SMTP provider:
Gmail may flag emails if:
SMTP is set as
[email protected]Workflow sends from
[email protected]
Outlook and Yahoo may block sending entirely if:
SMTP is Outlook/Yahoo
Workflow sends from a Gmail address
Rule:
👉 The SMTP email address and workflow “From” email must match exactly.
Daily Sending Limits Reached
Some providers enforce daily limits.
Example:
Gmail: ~150 emails per day
What happens:
Emails fail immediately once the limit is reached.
Failed emails are not retried automatically.
Fix:
Pause workflows until the limit resets, or
Upgrade to a business email provider (recommended).
Frequently Asked Questions (FAQ)
Are there sending limits when using Gmail?
Yes. Gmail typically allows about 150 emails per day. Exceeding this limit causes email failures or spam flagging.
Can I use different emails in workflows than my SMTP email?
No. Using different addresses increases the risk of spam filtering or outright blocking by Gmail, Outlook, or Yahoo.
Does Kyrios receive email analytics from all SMTP providers?
No. Only Mailgun reports full email statistics back into Kyrios. Other providers may not return delivery, open, or click data.
What should I do if Outlook or Yahoo emails are not sending?
Ensure the workflow sender email exactly matches the SMTP provider email.
Why is Kyrios Systems recommended as the SMTP provider?
Because it:
Provides direct email analytics inside Kyrios
Has fewer deliverability issues
Is designed specifically for workflow and automation sending