Let us know how it goes and share your findings. You can also refer to the Adobe article Validating digital signatures, Adobe Acrobat This identifies the owner of the digital certificate that has been used when signing the document.ĥ) Mark the certification path, click the 'Trust' tab and then 'Add to Trusted Identities'.Ħ) Answer 'OK' to any security question that follows.ħ) Check the field for 'Use this certificate as a trusted root' and click 'OK' twice to close this and the next window.Ĩ) Click 'Validate Signature' to execute the validation. You can resolve this problem by performing the following steps. You may try the following steps and see if this helps:ġ) Right-click on the ‘validity unknown’ icon and click on ‘Validate Signature’.Ģ) You will get the signature validation status window, click on ‘Signature Properties’.Ĥ) Verify that there is a certification path. After opening a signed document in Acrobat Reader DC do you get an error message that says 'The validity of your signature is UNKNOWN', as shown in this picture One possible reason is that the 'Belgium Root CAs' are not yet trusted by Acrobat Reader.
PDF SIGNATURE VALIDITY UNKNOWN PDF
Is it specific to one PDF file or with all the PDF files? Is it a Mac or Windows machine and what is the version of operating system installed? What is the dot version of Adobe Reader installed? To identify refer to Identify the product and its version for Acrobat and Reader DC Is it possible to post a screenshot of the error message you get? To share the screenshot, refer to the steps mentioned in the article
Additional status details appear in the Signatures panel and in the Signature Properties dialog box. When Digital Signatures are validated, an icon appears in the document message bar to indicate the signature status. As per the description above, I can understand that you are not able to validate a signature in a PDF file, Is that correct?