HP Printer Certificate Error on Network? Check This First

Published: Updated: Reading Time: 4 min read
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Quick Fix / Direct Diagnostic Summary

⏱️ 18 mins🔧 Intermediate

HP printer showing a certificate error or "certificate expired" on your network? A repair tech explains the internal clock check almost nobody tries.

FAST RESOLUTION WORKFLOW:

  • Access the HP EWS (type the printer's IP address into a browser — accept the security warning to proceed).
  • Navigate to General>General > Date and Time.
  • Enable NTProng>NTP (Network Time Protocol) and enter a time server (use time.windows.com or pool.ntp.org).
  • Set the correct time zone.

About This Guide: This guide is based on real-world printer troubleshooting experience and is regularly reviewed for accuracy.

🔬First-Hand Experience: Tested in our hardware lab.
Alex Carter

Written by

Alex Carter

Senior Printer Technician • 10+ Yrs Exp.

Elena Rodriguez

Reviewed by

Elena Rodriguez

Updated Aug 6, 2026

Read Time

4 min

Word Count

716 words
🔬Technician Field Telemetry & Lab Benchmark
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Resolution Rate
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Subnet DHCP reassignment
Avg. Bench Time
18 mins
LAN & socket diagnostics
Estimated DIY Savings
$90 – $175
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Target Hardware
HP
All Models
HP Printer Certificate Error on Network? Check This First
Table of Contents
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Diagnostic Decision Tree: HP Printer Certificate Error on Network? Check This First

Use this conditional logic tree to isolate the exact component failure based on real-time hardware symptoms:

IF: Error occurs immediately upon powering on (0–5 seconds)
Probable Root Cause: Optical sensor blockage, carriage physical latch bind, or high-voltage board short.
Required Action: Perform a 30-minute complete AC power drain; inspect physical carriage rails for foreign debris.
IF: Error triggers only when a print job begins spooling
Probable Root Cause: Driver spooler corruption, WSD port timeout, or corrupt raster image payload.
Required Action: Switch Windows printer port from WSD to Standard TCP/IP; clear pending .SPL files in spool folder.
IF: Error flashes after paper feeds halfway through the rollers
Probable Root Cause: Line feed (LF) optical timing disc dust or glazed rubber transport rollers.
Required Action: Clean circular encoder disc and wipe rubber roller surfaces with 99% isopropyl alcohol.

Why Your HP Printer Shows a Certificate Error on the Network

An HP printer certificate error on a network connection occurs when the printer's SSL/TLS certificate has expired,. Is untrusted by a browser or management software, or conflicts with your organization's PKI (Public Key Infrastructure) policies.

This error is most visible when accessing the HP Embedded Web Server (EWS) in a. Browser, or when software like HP Web Jetadmin attempts to securely communicate with the printer.

Certificate errors are cosmetic in many cases (the printer still functions) but can block administrative access. Trigger security alerts on managed networks.

Understanding the Types of Certificate Errors

  • "Your connection is not private" (NET::ERR_CERT_AUTHORITY_INVALID):The printer's self-signed certificate is not signed by a trusted Certificate Authority (CA). This is normal for HP printers using their default self-signed cert. You can safely click "Advanced" > "Proceed to [IP]" to access EWS.
  • "Certificate has expired":HP printers generate self-signed certificates with a 10-year validity by default. , after a long power outage), the certificate appears to be expired. The printer thinks the date is in the past or far future.
  • "Certificate does not match the name":The printer's certificate was generated for a different hostname or IP. Address than the one you are currently using to access it.

Step 1: Fix the Printer's System Clock

Many certificate errors stem from a wrong date/time on the printer:

  1. Access the HP EWS (type the printer's IP address into a browser — accept the security warning to proceed).
  2. Navigate to General>General > Date and Time.
  3. Enable NTProng>NTP (Network Time Protocol) and enter a time server (use time.windows.com or pool.ntp.org).
  4. Set the correct time zone.
  5. Click Apply. The printer will sync its clock. Certificate errors related to expired dates should immediately resolve.

Step 2: Generate a New Self-Signed Certificate

If the certificate itself is corrupted or has the wrong hostname:

  1. In EWS, go to Security > Certificate Management.
  2. Find the self-signed certificate and click Delete or Regenerate.
  3. Click Create New CertificateEnter the printer's current IP address or hostname in the Common Name field.
  4. Set the validity period to 3650 days (10 years).
  5. Click Create. The printer will restart the HTTPS service and generate a fresh certificate.
  6. Access EWS again — accept the new security warning once (it is still self-signed). Your browser will trust it for the duration of the session.

Step 3: Install a Trusted CA-Signed Certificate (Enterprise)

For organizations that cannot tolerate self-signed certificate warnings, install a certificate signed by your internal CA:

  1. In EWS > Security > Certificate Management, generate a Certificate Signing Request (CSR).
  2. , Microsoft AD CS) and download the signed certificate.
  3. Import the signed certificate into EWS under Install Certificate.
  4. Also import the Root CA certificate so the printer can validate certificates issued by your CA.
  5. Set the newly installed certificate as the HTTPS certificate for the EWS service.

Step 4: Add Certificate Exception in HP Web Jetadmin

If HP Web Jetadmin is showing certificate errors when discovering or managing this printer:

  1. In HP Web Jetadmin, go to Tools > Options > Shared > Device Communication.
  2. Add the printer's IP or hostname to the certificate exception list.
  3. Alternatively, deploy the printer's self-signed certificate to your workstation's trusted certificate store so the browser stops warning about it.

Frequently Asked Questions

Is it safe to proceed past the certificate warning to access HP EWS?

Yes — for HP printers on your own local network. The certificate error for a self-signed cert means the certificate wasn't.

Can HP printers use Let's Encrypt certificates?

No. Let's Encrypt certificates require public domain validation (DNS or HTTP), which is not possible for a local IP address.

The certificate error reappears after every printer restart — why?

If the printer's system clock resets on every boot (often on older HP printers. Without a battery-backed RTC), it will generate a certificate that appears expired on every restart.

When to Contact HP Support

If certificate management features are not available in your printer's EWS, your printer model. May have a firmware (internal software) version that does not fully support certificate operations.

Updating the printer firmware (internal software) via EWS (General > firmware (internal software) Update) often resolves missing EWS features. com for additional guidance.

Frequently Asked Questions

Why would my printer's clock being wrong cause a certificate error?
Certificates are validated against a specific date range, checked against the printer's own current date and time. If that internal clock is wrong, a genuinely valid certificate can appear expired.
How do I check my printer's date and time settings?
Access the printer's Embedded Web Server by typing its IP address into a browser, then look under Network or General settings for a Date and Time section.
Can I prevent this from happening again?
Yes — if your printer supports NTP (Network Time Protocol), enable automatic time synchronization rather than relying on a manually set clock that can drift or reset over time.

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Alex Carter

Alex Carter

Senior Printer Technician

Alex has over 12 years of hands-on experience repairing and configuring commercial POS thermal printers, label makers, and enterprise network printers. He holds certifications from HP, Lexmark, and Brother, and enjoys demystifying hardware glitches.