Connection - SMTP
The SMTP Connection stores the address, sign-in and security settings that the Email - Send Task and the Email Trigger use to connect to a mail server over Simple Mail Transfer Protocol (SMTP). The Email - Send Task sends email through it, and the Email Trigger forwards matching email through it.
Common settings
The Common settings and Proxy tabs are the same for every Connection type that has them; see Common settings and Proxy.
Test
Opens the Test SMTP Connection window. Enter an address in From email and in To email, then click Test. The Server connects with the settings of this Connection and sends a real message, with the subject "Test subject (from VisualCron)", to the To email address. With "Gmail OAuth", click Authenticate before you test.
Main settings
These fields are on Connection settings -> Main settings.
The Connection settings tab holds three tabs: Main settings, Encryption and Proxy.
Address
The DNS name or IP address of the SMTP server. Enter the full DNS name, not a short server name.
Port
The port of the SMTP server. A new Connection starts at "25". The port must match the settings on the Encryption tab. Mail servers usually use "25" without encryption, "587" with "TLS" and "Explicit", and "465" with "Implicit".
Default settings for some servers
Exchange
- Address: the full DNS name of the Exchange server
- Port: "587"
- Cryptographic protocol: "TLS"
- Security mode: "Explicit"
Office 365 (Deprecated after April 2026 by Microsoft)
Main settings
- Address: smtp.office365.com
- Port: 587
Encryption
- Cryptographic protocol: TLS (1.2)
- Security Mode: Explicit
Gmail
- Address: "smtp.gmail.com"
- With "Default" authentication: Port "465", Cryptographic protocol "TLS", Security mode "Implicit"
- With "Gmail OAuth": Port "587", Cryptographic protocol "TLS"
Amazon SES
- Address: "email-smtp.us-east-1.amazonaws.com", or the Amazon SES SMTP address of your region
- Port: "465"
- Cryptographic protocol: "TLS" (TLS 1.2)
- Security mode: "Implicit"
Authentication
Authentication type
How the Connection logs on to the server:
- "Default": a user name and password
- "Gmail OAuth": Google OAuth, for Gmail and Google Workspace accounts
The Email Trigger forward action always logs on as with "Default". To forward email from the Email Trigger, use an SMTP Connection with "Default" authentication.
Anonymous
Sends email without logging on. When selected, Username and Password are unavailable. Shown only with "Default".
Username
The user name of the email account. Required unless Anonymous is selected. With "Gmail OAuth", this field is labeled Application Id and holds the client ID of your Google OAuth client.
Password
The password of the email account. With "Gmail OAuth", this field is labeled Client secret and holds the client secret of your Google OAuth client.
Setup app
Shown with "Gmail OAuth". Opens the Google API Console in the web browser, where you create the OAuth client.
Authenticate
Shown with "Gmail OAuth". Opens the Google sign-in page in the web browser. When sign-in succeeds, the authorization is saved in the Connection, and the Server sends email as the Google account that signed in.
App settings
Shown with "Gmail OAuth". Of the fields in this group, only Redirect Url is used with Google. Tenant Id, Tenant Primary Domain, Tenant Name and Auto-accept server certificates are not used.
Redirect Url is the address that receives the reply from Google after sign-in, on the computer that runs the Client. It is required for Authenticate. Enter a local address such as "http://localhost:9999", and add the same address as an authorized redirect URI in the Google OAuth client.
To set up "Gmail OAuth", complete the following steps:
- In Authentication type, select "Gmail OAuth".
- Click Setup app. The Google API Console opens.
- In the Google API Console, create an OAuth client ID.
- Add the address that you will enter in Redirect Url as an authorized redirect URI of the OAuth client.
- Enter the client ID in Application Id.
- Enter the client secret in Client secret.
- Enter the redirect address in Redirect Url.
- On the Encryption tab, select "TLS" in Cryptographic protocol.
- On Main settings, enter "587" in Port.
- Click Authenticate.
- In the web browser, sign in with the Google account that sends the email.
- Allow access.
- Click OK.
The Connection now sends email as that Google account.
Encryption
With "Default" authentication, the Email - Send Task, the Email Trigger forward action and Test use every setting on this tab. With "Gmail OAuth", the Email - Send Task and Test use only Cryptographic protocol.
Cryptographic protocol
- "No encryption": plain SMTP; the Allowed SSL/TLS versions group is unavailable
- "SSL": SSL encryption; selects SSL version 2 and SSL version 3 in Allowed SSL/TLS versions
- "TLS": TLS encryption; selects TLS version 1 to TLS version 1.3 in Allowed SSL/TLS versions
With "Gmail OAuth", "TLS" connects in plain text and then switches to encryption, so it needs port "587". "SSL" encrypts from the start, as on port "465".
With "Default" authentication, the Server offers the mail server only the versions selected in Allowed SSL/TLS versions. Selecting "SSL" selects only SSL version 2 and SSL version 3, which are obsolete. A mail server that accepts only TLS refuses the connection, and Jobs that use the Connection fail. Select "TLS", or also select the TLS versions that the mail server supports.
Security mode
Used with "Default" authentication.
- "Explicit": the connection starts in plain text and then switches to encryption
- "Implicit": the connection is encrypted from the start
On a new Connection, selecting "Implicit" changes Port to "990". For an SMTP server that uses implicit encryption, change Port to "465".
Allowed SSL/TLS versions
The SSL and TLS versions that the Server offers with "Default" authentication. Some servers accept only certain versions.
- SSL version 2
- SSL version 3
- TLS version 1
- TLS version 1.1
- TLS version 1.2
- TLS version 1.3
SASL Mechanisms
The SASL logon mechanisms that the Server may use with "Default" authentication when Anonymous is cleared. All three are selected on a new Connection.
- NTLM
- DIGEST-MD5
- CRAM-MD5
With "Default" authentication, the Server does not check the SMTP server's certificate. "SSL" and "TLS" encrypt the session, but do not confirm that the server is the one named in Address. Use the Connection only over a network that you trust.
Proxy
The Server does not use the settings on this tab for an SMTP Connection. The Email - Send Task, the Email Trigger forward action and Test connect to the mail server directly.
Troubleshooting
No authentication method enabled from those supported by the server
If the server accepts email without a logon, select Anonymous on the Main settings tab.
Error 96260 when sending email or clicking Test
In Address, enter the full DNS name or the IP address of the server, not a short server name.
User authentication failed: Unaccepted server reply for command AUTH PLAIN (Gmail)
You need to allow less secure apps to access your Gmail account Google may block sign-in attempts from some apps or devices that do not use modern security standards. Since these apps and devices are easier to break into, blocking them helps keep your account safe.
To disable this security feature:
- Sign in to Gmail
- Click here to access Less Secure App Access in My Account.
- Next to “Allow less secure apps: OFF,” select the toggle switch to turn ON.
This setting may not be available for:
Accounts with 2-Step Verification enabled: Such accounts require an application-specific password for less secure apps access.
G Suite users: This setting is hidden if your administrator has locked less secure app account access.