Mailforge and Infraforge mailboxes can be connected directly to third-party applications, email clients, and custom integrations using SMTP and IMAP.
You do not need an active Salesforge subscription to use your mailbox credentials with an external application. You can connect your mailboxes to tools such as Apollo, Clay, custom applications, email clients, or scripts that support standard SMTP and IMAP authentication.
This guide explains how to retrieve your connection details, configure encryption, understand authentication requirements, and work with the limitations of direct mailbox connections.
Each mailbox has its own connection credentials.
You will need the following information to configure an external application:
SMTP server hostname
SMTP port
SMTP username
SMTP password
IMAP server hostname
IMAP port
IMAP username
IMAP password
Where to find this info?
You will need to go to Mailbox tab, click 'Export Mailboxes' at the top of the screen, Export to Salesforge > download CSV file, this will download a CSV file. You can open that file and see all the information
The connection settings differ between Mailforge and Infraforge.
Mailforge uses shared mail infrastructure.
Setting | Configuration |
|---|---|
SMTP hostname | Mail server hostname assigned to your mailbox |
SMTP port | 587 |
SMTP encryption | STARTTLS |
IMAP hostname | Mail server hostname assigned to your mailbox |
IMAP port | 993 |
IMAP encryption | Implicit TLS (IMAPS) |
Authentication | Username and password |
Recommended SMTP configuration:
Port: 587
Encryption: STARTTLS
Authentication: Enabled
Username: Your full mailbox email address
Password: Your mailbox password
IMAP configuration:
Port: 993
Encryption: SSL/TLS (implicit TLS)
Authentication: Enabled
Username: Your full mailbox email address
Password: Your mailbox password
Infraforge uses dedicated mail infrastructure and dedicated IP allocation.
Setting | Configuration |
|---|---|
SMTP hostname | Dedicated mail server hostname assigned to your mailbox |
SMTP port | 465 |
SMTP encryption | Implicit TLS |
IMAP hostname | Dedicated mail server hostname assigned to your mailbox |
IMAP port | 993 |
IMAP encryption | Implicit TLS (IMAPS) |
Authentication | Username and password |
Recommended SMTP configuration:
Port: 465
Encryption: SSL/TLS (implicit TLS)
Authentication: Enabled
Username: Your full mailbox email address
Password: Your mailbox password
IMAP configuration:
Port: 993
Encryption: SSL/TLS (implicit TLS)
Authentication: Enabled
Username: Your full mailbox email address
Password: Your mailbox password
The recommended port depends on the infrastructure product:
Mailforge: Use port 587 with STARTTLS.
Infraforge: Use port 465 with implicit TLS.
These are different configurations. Do not apply Infraforge's SMTP settings to Mailforge or vice versa.
Mailforge and Infraforge use standard username-and-password authentication for direct SMTP and IMAP connections.
The following authentication methods are supported:
Full mailbox email address as the username.
Mailbox password as the password.
OAuth is not supported for direct Mailforge or Infraforge SMTP/IMAP authentication. XOAUTH2 is not available.
There is also no separate app-specific password or restricted-credential feature.
You should therefore use the credentials assigned to the mailbox when connecting an external application.
Keep your mailbox credentials secure and only provide them to applications and services you trust.
Forwarding can be configured through the available Mailforge or Infraforge mailbox management functionality.
Forwarding settings are managed through the mailbox configuration and can have the following statuses:
Pending
Active
Failed
There is no separate email-confirmation step for verifying a forwarding address.
You can check the forwarding configuration and its status in the mailbox settings.
Automatic copying of SMTP-sent messages into the Sent folder is not guaranteed.
SMTP handles message submission, but saving a copy in the Sent folder is a separate mailbox operation. This behaviour depends on the mail server and the sending application.
If your external application sends messages through SMTP without performing an additional IMAP operation, the messages might not appear in the mailbox's Sent folder.
Recommended approach:
If keeping a record of sent messages is important, use an application that supports saving sent messages to the mailbox through IMAP APPEND.
Alternatively, check whether your third-party sending application has an option to save sent messages to the connected mailbox.
We recommend testing this behaviour before relying on it for your daily workflow.
Mailforge and Infraforge do not require IP allowlisting for direct SMTP or IMAP connections.
There is no application-level restriction requiring connections to originate from a specific IP address or predefined IP range.
This means that external applications, scripts, and services can connect using valid mailbox credentials without first registering their IP addresses.
Connecting a mailbox directly to an external application gives that application access to the mailbox through standard email protocols.
However, direct SMTP/IMAP access does not provide the same functionality as integrating the mailbox with Salesforge.
With valid SMTP and IMAP credentials, an external application can:
Send messages through SMTP.
Retrieve messages through IMAP.
Read mailbox folders.
Manage mailbox messages, depending on the application's IMAP capabilities.
Access mailbox data without using Salesforge.
Direct SMTP/IMAP connections do not automatically provide Salesforge campaign tracking or delivery-event integrations.
For example, when sending through a third-party application:
Salesforge campaign analytics will not automatically track those messages.
Salesforge campaign bounce statuses will not be populated by the external application's SMTP activity.
You will not automatically receive Salesforge campaign delivery or bounce events for those messages.
Your external application is responsible for handling SMTP responses, delivery failures, and any available bounce notifications.
A message being successfully accepted by the SMTP server does not guarantee that it reaches the recipient's inbox.
You can use direct mailbox credentials with custom applications and server-side integrations, provided the runtime supports the required network protocols.
For example, Cloudflare Workers can use their TCP Sockets API for outbound TCP connections.
On the Mailforge and Infraforge side, there are no Cloudflare-specific IP allowlisting or SMTP/IMAP restrictions.
However, Cloudflare's own outbound networking policies determine which ports are available to Workers.
The following ports are relevant:
Protocol | Port | Encryption |
|---|---|---|
Mailforge SMTP | 587 | STARTTLS |
Infraforge SMTP | 465 | Implicit TLS |
Mailforge / Infraforge IMAP | 993 | Implicit TLS |
Cloudflare's platform restrictions should be checked separately, and we recommend testing the actual connection from a deployed Worker before implementing the integration.
Note: Primeforge is different. Primeforge mailboxes use Google Workspace or Microsoft 365 infrastructure and have different authentication requirements. Direct SMTP/IMAP username-and-password access is not supported through the Primeforge integration. Use the appropriate OAuth-based integration instead.
If your external application cannot connect to a mailbox, check the following:
Verify the hostname: Make sure you are using the mail server hostname assigned to your mailbox.
Check the port: Use port 587 for Mailforge SMTP or port 465 for Infraforge SMTP. Use port 993 for IMAP.
Check encryption: Make sure you have selected STARTTLS for Mailforge SMTP and implicit TLS for Infraforge SMTP and IMAP.
Verify credentials: Use the full mailbox email address as the username and the correct mailbox password.
Check authentication settings: Ensure SMTP authentication is enabled.
Check external restrictions: Your application, hosting provider, or network may restrict outbound connections to SMTP or IMAP ports.
Test the connection independently: If possible, test the same credentials using a standard email client to determine whether the issue is specific to your application.
If the issue persists, contact support with the affected mailbox, the application you are connecting from, the protocol and port, and the exact connection error.
Can I use Mailforge and Infraforge without a Salesforge subscription?
Yes. You can connect Mailforge and Infraforge mailboxes directly to external applications using SMTP and IMAP credentials. An active Salesforge subscription is not required for direct mailbox connectivity.
Can I connect Mailforge and Infraforge to Apollo, Clay, or my own application?
Yes, provided the external application supports standard SMTP and/or IMAP authentication and the required connection settings.
Do Mailforge and Infraforge support OAuth?
No. Direct Mailforge and Infraforge SMTP and IMAP authentication use a mailbox username and password.
Will messages sent through an external application appear in my Sent folder?
Not necessarily. This depends on whether the sending application saves a copy to the mailbox using IMAP. We recommend testing this before relying on automatic Sent-folder synchronization.
Is there an IP allowlisting requirement?
No application-level IP allowlisting requirement has been identified for direct Mailforge or Infraforge SMTP/IMAP connections.
Is there a daily sending limit?
Mailforge mailboxes have a server-enforced limit of 100 messages per mailbox per day. Using an external application does not bypass this limit.
Will Salesforge track emails sent externally?
No. Emails sent outside Salesforge are not automatically included in Salesforge campaign analytics or campaign-level bounce and delivery tracking.
