Self-signed certificate for ePOS printers

Estimated reading: 3 minutes 21 views

Introduction

Some ePOS printer models can connect directly to Odoo without an IoT system, but they require HTTPS to ensure a secure connection between the browser and the printer.

By default, accessing the printer’s IP address with HTTPS will trigger a browser warning (untrusted certificate). You can bypass this warning temporarily, but for a long-term and secure solution, you should generate, export, and import a self-signed certificate into your browser or device.

  • The temporary bypass only lasts until you close the browser window.
  • For continuous use, follow the certificate generation and import steps.

Step-by-Step Instructions

 

1. Temporary Workaround

  1. Open your browser and go to the printer’s IP address in HTTPS, e.g. https://192.168.1.25.
  2. On the warning page, click Advanced → Proceed to [IP address] (unsafe).
  3. Log in with your printer credentials:
    1. ID: epson
    2. Password: your printer’s serial number
  4. This will temporarily allow HTTPS connection until the browser window is closed.

2. Generate a Self-signed Certificate

  1. Log in to your printer’s web interface.
  2. Go to Authentication → Certificate List.
  3. Click Create to generate a certificate.
    1. Common Name: auto-filled (if not, enter the printer’s IP address).
    2. Validity Period: select number of years (e.g. 5).
  4. Click Create.
  5. Restart the printer (manually or via Reset option).

 

3. Export the Self-signed Certificate

  • Go to the Certificate List and select your newly created certificate.
  • Click Export to download it to your computer/device.

 

4. Import the Self-signed Certificate into Your Browser/OS

Follow the instructions for your operating system:

  • Windows 10 & Linux OS – Import via system certificate manager.
  • Mac OS – Import via Keychain Access.
  • Android OS – Import via Security → Encryption & credentials → Install certificate.
  • iOS – Import via Settings → General → About → Certificate Trust Settings.

 For other systems/browsers:

  • Search online for:
    • “Export SSL certificate [your OS/browser]”
    • “Import SSL certificate root authority [your OS/browser]”

5. Verify the Certificate

  1. Open your browser and go to https://[printer-ip].
  2. If installed correctly:
    1. You will no longer see a warning page.
    2. The browser address bar will show a padlock icon.

Tips

  • Only generate one certificate per printer. Creating another will invalidate the previous one.
  • Save your exported certificate safely for reuse across multiple devices.
  • If using multiple POS terminals, import the certificate into each terminal’s browser.
  • Always restart the printer after creating the certificate to apply changes.

Key Benefits

  • Secure communication between POS and ePOS printers.
  • Browser trust without constant warning pages.
  • Long-term compatibility with Odoo and HTTPS requirements.
  • Centralized management of printer security across devices.

Related Articles

Configuration - Previous Secure connection(HTTPS) Next - Configuration Shop features

Leave a Reply

Your email address will not be published. Required fields are marked *

Learn how we helped 100 top brands gain success