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AWhitbread
AWhitbread
Participant
June 19, 2026
Question

Some Adobe users in my company see when they opened signed documents - "The validity of the document certification is UNKNOWN. The author could not be verified"

  • June 19, 2026
  • 1 reply
  • 0 views

After a document has been signed and saved as a certified copy by one user, some employees are getting this message at the top when they open the document themselves “The validity of the document certification is UNKNOWN. The author could not be verified.” whereas others in the company don’t get this and see the correct banner that says its a certified document. We all have the same licenses that are managed by our employer.

    1 reply

    Amal Jaiswal
    Community Manager
    Amal JaiswalCommunity Manager
    Community Manager
    June 19, 2026

    Hi there 


    This error occurs because the signer's digital certificate isn't in your Adobe Acrobat list of trusted identities. To fix it, you need to manually trust the certificate and validate the signature.


    Try the steps below and see if that works:

    1. Right-click (or Ctrl+click on Mac) the signature with the unknown validity and select Show Signature Properties.

    1. In the dialog box that appears, click the Show Signer's Certificate button.

    1. Go to the Trust tab, then click Add to Trusted Certificates.

    1. Click OK if prompted, and ensure you check the box that says "Use this certificate as a trusted root".

    1. Click OK on the trust windows, then click Validate Signature.


    For more information, please check the help pages listed below:

    https://adobe.ly/4aaFYNi

     https://adobe.ly/4vl6USP 


    ~Amal

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