Replace CA certificate

[Wally3460]

My CA certificate on my HP LaserJet Pro M277dw have expired and I need to replace it.
I got the pem/base64 file, but when I try to upload the new certificate it asks for a username and password, which is not the administrator credentials.
I have no clue what those can be and I can not see anywhere to set those credentials.

I have tried to do a permanent storage init on the device, but that did not change the CA certificate.

[Hawks_Eye]

Hi @Wally3460 

Welcome to the HP Support Community!

Thanks for posting your query! We're here to help you get back up and running.

I'm afraid, we shall not be able to assist you with queries that include instructions or directions intended to bypass or subvert security measures, including passwords, locking mechanisms, fingerprint scans, etc., or to bypass any safety measures.

 If you would like help resetting the password on your product, please contact HP support in your region. 

Please click on this link https://www.hp.com/us-en/contact-hp/ww-phone-assist.html and select your country and login/create an account to get the phone number to reach our phone support team. 

Take care, and have an amazing day!

Regards, 

Hawks_Eye

[Wally3460]

It is my own printer and I have the administrator password.

I have been able to remove the CA certificate, because that required no credentials, but installing a new one requires an unknown password. Unknown as in nowhere to be found, nowhere be defined, nowhere to be set.

It seems like the GUI/firmware is either missing this access level or page to actually manage these credentials.

I would say it is a bug.

[Hawks_Eye]

Hi @Wally3460 

Thanks for sharing the details of what you’ve tried so far. Let’s go step by step to address the certificate replacement issue on your HP LaserJet Pro M277dw:

Accessing the Embedded Web Server (EWS)

• Open a browser on your Windows PC and enter the printer’s IP address.
• Log in with the administrator credentials you already have.

Navigating to Security Settings

• In the EWS, go to the Networking or Security tab (depending on firmware version).
• Look for Certificates or CA Certificates management.

Uploading the New Certificate

• When you attempt to upload the new PEM/Base64 certificate, the printer may prompt for credentials beyond the administrator login.
• This prompt is typically for the Private Key password associated with the certificate file itself, not a separate printer account.
• If your certificate was generated with a password-protected private key, you’ll need to enter that password here. If no password was set during certificate creation, leave the field blank and try again.

Permanent Storage Initialization

• Performing a storage init clears certain stored data but does not reset certificate handling. That’s why the expired CA certificate remained unchanged.
• The correct path is through the EWS certificate management page.

Verification After Upload

• Once uploaded, confirm the certificate is listed under Installed Certificates.
• Restart the printer to ensure the new certificate is applied.

Note: The password prompt you’re seeing is not for another hidden printer account. It’s tied to the certificate file itself. If you don’t recall setting one, try leaving the field blank. If the certificate was generated by a CA or tool that enforces a password, you’ll need that specific password to complete the upload.

If my response helped, please mark it as an Accepted Solution! ✅ It helps others and spreads support. 💙 Also, tapping "Yes" on "Was this reply helpful?" makes a big difference! Thanks! 😊

Take care, and have an amazing day!

Regards, 

Hawks_Eye

[Wally3460]

Thanks for your reply, Hawks_eye.

Sadly you are on the run track here.

A CA certificate is requiring a public part  of the certificate and not the private one.

This means there is no password protection in the certificate.

I found this manual for an older version of my printer firmware and page 4 have a list of ways to get the certificate, which proves it is the public part I need.

https://h10032.www1.hp.com/ctg/Manual/c04574887.pdf

[Hawks_Eye]

Thank you for clarifying further @Wally3460  

Since you’re working with a CA certificate (which only contains the public portion), the password prompt you’re seeing is not expected in that context. Let’s go through the precise steps that should allow you to replace the CA certificate on your HP LaserJet Pro M277dw:

Accessing the Embedded Web Server (EWS)

1. On your Windows PC, open a browser and enter the printer’s IP address.
2. Log in with the administrator credentials you already have.

Navigating to Certificate Management

1. In the EWS, go to the Networking or Security tab (depending on firmware version).
2. Look for Certificates or CA Certificates.

Replacing the CA Certificate

1. Select the option to Import/Upload CA Certificate.
2. Browse to the certificate file (usually in .cer or .crt format, Base64/PEM encoded).
3. Since CA certificates are public-only, no private key or password should be required. If the interface still prompts for a password, leave the field blank and proceed.

Confirming Installation

1. After upload, verify that the new CA certificate appears in the list of installed certificates.
2. Restart the printer to ensure the certificate is applied.

Additional Notes

• If the firmware is prompting for a password where none should exist, it may be a firmware handling issue. In that case, try converting the certificate to a different supported format (for example, DER vs. PEM) and re-upload.
• Ensure you are uploading the correct CA certificate type (not a device certificate or identity certificate, which would require a private key).

This process should allow you to replace the CA certificate without needing any hidden credentials. If the prompt persists even with a proper CA certificate file, the workaround is usually to re-export the certificate in a format the printer accepts and retry the upload.

Regards,

Hawks_Eye

[Wally3460]

---

@Hawks_Eye wrote:

Replacing the CA Certificate

1. Select the option to Import/Upload CA Certificate.
2. Browse to the certificate file (usually in .cer or .crt format, Base64/PEM encoded).
3. Since CA certificates are public-only, no private key or password should be required. If the interface still prompts for a password, leave the field blank and proceed.

Part 3 above is where the issue occur.
A popup asking for credentials will appear and no matter what I enter I can not get the printer to accept it.
I have tried....

- the administrator and password for accessing the web interface

- no username and no password

- admin as username and no password

- administrator as username and no password

- admin as username and admin as password

- all thinkable versions of the above with capitalized letters too

I can import the certificate in other places, like NAS drive, browsers and so on, without a credentials set.

[Pisces_Orca]

Hello

I would like to confirm with you what the current firmware version of this printer is.

In addition, we recommend that you check and upgrade the printer firmware to the latest official version. Updating the firmware will obtain the latest root CA certificates, which can effectively resolve various network connection and encrypted communication issues caused by certificate problems, and ensure the proper functioning of the device.

Thank you for your cooperation!

[Wally3460]

Thanks for your reply, Pisces_Orca.

I am on firmware datecode 20220414, which is the newest available.

Your comment gave me the idea that reapplying the firmware might be able to fix it, but alas it did not change anything. The CA certificate is still not updated, which makes sense that a firmware would not, since a company might have installed the ones they trust and a firmware update should not change that.