FAQ
Frequently Asked Questions
Everything you need to know about connecting your devices to DeviceSMTP, configuring ports and encryption, managing credentials and monitoring delivery.
General
About DeviceSMTP
What it is, what it does and who it is for.
What is DeviceSMTP?
DeviceSMTP is a specialist SMTP gateway built for physical hardware: printers, security cameras, alarm panels, industrial controllers, IoT sensors and any other device that sends email alerts or notifications. Rather than relying on your device’s fragile built-in mail support, you point it at the DeviceSMTP gateway. We handle authentication, TLS encryption, delivery retries and logging so your device mail arrives reliably.
Who is DeviceSMTP for?
DeviceSMTP is for IT administrators, facilities managers and anyone responsible for keeping hardware notifications working. If you manage a building full of printers and cameras, a factory floor of PLCs, or even a single network device that sends alerts, DeviceSMTP gives you one stable, monitored relay for all of it.
Why does my printer need an SMTP gateway?
Many printers can technically send email, but their built-in SMTP client often breaks in practice. Modern mail providers like Gmail and Microsoft 365 dropped the basic username-and-password login that older printer firmware relies on, and ISPs routinely block outgoing mail ports on business lines. DeviceSMTP gives your printer one stable, standards-based destination that is specifically built to accept and relay its mail — no firmware update required.
Devices & Compatibility
What hardware can I connect?
DeviceSMTP works with any device that speaks standard SMTP — no special firmware or code required.
Can I use DeviceSMTP with security cameras and surveillance systems?
Yes. Security cameras and NVRs typically have an SMTP screen for sending motion-alert or snapshot emails. Enter the DeviceSMTP hostname, one of the supported ports (587, 465 or 2525) and your per-device credentials, and the camera sends through our gateway. You can then see every alert in your activity log and confirm it was delivered. See the Security Cameras use case for details.
Can I use DeviceSMTP with industrial equipment and PLCs?
Yes. Industrial controllers, PLCs, SCADA systems and similar equipment that support SMTP-based notifications can use DeviceSMTP as their relay. Because we accept standard SMTP on multiple ports with both STARTTLS and implicit TLS, most firmware configurations are compatible without modification. See the Industrial Automation use case for guidance.
What other devices work with DeviceSMTP?
Any device or system that speaks standard SMTP works with DeviceSMTP: alarm systems, HVAC controllers, UPS units, network switches, server monitoring agents, IoT sensors, building management systems and more. If your device has an SMTP settings screen, it can use our gateway. Browse all use cases for specific examples.
Do I need to change my device’s firmware or write any code?
No. DeviceSMTP works with the SMTP settings your device already has. You enter our gateway hostname, choose a supported port, select TLS or SSL and enter your credentials. There is nothing to install, no SDK and no code to write. Our documentation includes step-by-step guides for common device types.
Configuration & Security
Ports, encryption and credentials
SMTP port choices, TLS support and how to issue per-device credentials securely.
Which SMTP ports do you support?
DeviceSMTP accepts connections on port 587 (submission with STARTTLS), port 465 (implicit SSL/TLS) and port 2525 (an alternative submission port with STARTTLS, useful when 587 is blocked by your network or ISP). You can use whichever port your device or firewall allows. See the SMTP configuration reference for the full details.
Do you support TLS and SSL encryption?
Yes. DeviceSMTP supports STARTTLS on ports 587 and 2525, and implicit TLS (sometimes labelled SSL) on port 465. Both methods encrypt the connection so credentials and message content are protected in transit. We recommend TLS 1.2 or 1.3; older protocol versions are not accepted. See all security features.
Can I use separate credentials for every device?
Yes. You can create a distinct SMTP username and password for each device in your fleet and label them meaningfully — for example “Camera — Warehouse entrance” or “Printer — Floor 3.” If a device is decommissioned or its credentials are compromised, you revoke only that one credential without affecting any other device. Learn more about per-device credentials.
Why are emails from my device sometimes blocked by my ISP or network?
Most ISPs and corporate networks block outbound connections on port 25 to prevent spam. This is a standard industry practice and it means a device trying to contact a mail server directly on port 25 will silently fail. DeviceSMTP solves this by accepting mail on ports 587, 465 and 2525, which are the designated submission ports that networks typically leave open for authenticated clients. If 587 is also blocked on your network, try port 2525 as an alternative.
Delivery & Monitoring
Logs, retries and dedicated IPs
How DeviceSMTP tracks and retries messages, and what visibility you get into every send.
How can I see whether my device actually sent an email?
Every message your devices send through DeviceSMTP is recorded in your activity log with a status (delivered, bounced or deferred), a timestamp and the recipient address. You can filter by device or time range to find any specific message. If a message bounced, the log shows the reason the receiving server gave, so you can diagnose the problem quickly. See monitoring features.
Do I need a dedicated IP address for my devices?
No, a dedicated IP is not required to use DeviceSMTP. Shared relay infrastructure is designed to maintain good sending reputation, so the vast majority of device mail reaches the inbox without a dedicated IP. A dedicated IP option is on our roadmap and planned for a future release — contact us if that is a requirement for your deployment and we can discuss your situation.
What happens if a receiving mail server is temporarily unavailable?
DeviceSMTP queues and retries deferred messages on a backoff schedule rather than dropping them immediately. If the destination server is temporarily unavailable or rate-limiting inbound mail, we keep trying for a standard retry window. You can see the current status of any deferred message in your activity log.
Give every device a reliable way to send email.
Create your DeviceSMTP account and connect your first device in minutes. No code, no firmware changes — just dependable delivery.