How Insightly connects to Microsoft services, and how to configure SMTP relay when multi-factor authentication blocks outgoing mail.
On this page:
What’s available
Several Microsoft features sync with Insightly. Most are available to all users, with some requiring a paid plan.
- Insightly Sidebar for Outlook – view customer information and save emails from your Outlook inbox. Requires your own Office 365 business plan subscription.
- OneDrive – link files to Insightly records. See Linking to Files in Cloud Storage.
- Azure AD / Entra ID single sign-on – see SSO / SAML.
Office 365 SMTP relay
ℹ️ This is specifically for accounts with multi-factor authentication enabled, where sending email through Insightly returns errors.
With MFA enabled on Microsoft 365 or Office 365, sending email through Insightly can fail. The fix is to set up an SMTP relay connector in Microsoft 365 or Office 365, then configure the account in Insightly to use it. SMTP relay is recommended specifically when you need to send to external recipients; if you don’t, Microsoft’s simpler “direct send” option is usually a better fit.
Requirements:
- A static (not dynamic) public IP address for the sending device or application.
- Port 25 open on your network and with your ISP.
- A connector configured in Exchange Online.
- If any sender lacks a Microsoft 365/Office 365 mailbox license, they’ll need at least an Exchange Online Protection license to send through the relay.
Setting up the connector
- Note the static public IP address the sending device or application will use.
- Sign in to the Microsoft 365 admin center, go to Settings > Domains, select your domain, and find the MX record’s “Points to” value. This is your MX endpoint (it looks like contoso-com.mail.protection.outlook.com).
- Confirm the destination domains are verified in Microsoft 365. Unverified domains can silently drop mail with no trace in the message trace tool.
- Go to Admin > Exchange to open the Exchange admin center, then Mail flow > Connectors.
- If no connector exists from your mail server to Microsoft 365, create one: click +, and on the first screen choose the options shown below.
- Name the connector, then on the next screen choose “By verifying that the IP address of the sending server matches one of these IP addresses” and enter the IP address from step 1. Leave the remaining fields at their defaults and save.
- In your domain registrar’s DNS settings, update your SPF record to include the static IP address, e.g. v=spf1 ip4:10.5.3.2 include:spf.protection.outlook.com ~all. Skipping this step risks mail landing in recipients’ junk folders.
- On the sending device or application, enter the MX endpoint from step 2 as the Server/Smart Host, with Port 25 and TLS enabled.
- Send a test email and confirm it arrives.
If your devices can authenticate with a certificate instead of an IP address, a certificate-based connector is also supported. The certificate’s domain name must match a domain registered in Microsoft 365, and the connector must be created with that same domain.
Setting up the Insightly side
- Go to User Settings > Email Accounts.
- Select your email service, or Other for a generic SMTP connection.
- Enter your server name (the MX endpoint from above) and continue.
- Enter the port number and login details, then click Add Account.
- Insightly sends a verification email; the account then appears in your Email Accounts list. If it doesn’t appear, or you see an error, check your inbox. If nothing arrives, try removing and re-adding the account.