Q: I want to add timestamps when adding digital signatures to PDF documents in PDF Studio. Do you have a list of timestamp servers available? A: In PDF Studio version 2020, we added support for SHA512 algorithm for communication with timestamp servers. This FreeTSA – Guide recommends using SHA-512. SHA-512 is part of SHA-2 (read […]
Category: Digital Signatures
Verifying and adding digital signatures to a PDF document
New “Fast Sign” Signature Stamps
The new Fast Sign tool, introduced in PDF Studio 2018, allows you to create electronic signature stamps that can be easily applied to documents. The Fast Sign signature stamp is a graphical representation of a signature on pen and paper such as an image or drawing. The stamps can be created using a signature font, […]
Creating Self-Signed Digital IDs for signing PDF documents
Q: How to create self-signed digital IDs in PDF Studio? A: In order to sign documents, you must first have a digital ID. If you do not have an existing ID, you can use PDF Studio to create a new digital ID to be used when signing documents. When creating a digital ID with PDF Studio, it is considered a “Self-Signed Digital ID” which means that it was not issued by […]
How to Avoid Adobe Appearance Integrity Report To Show Digital Signature as Invalid
Q: When I get signed PDFs back from a customer and check the digital signature using Adobe’s Appearance Integrity Report in the signature panel I get a list of error codes in the document. How can I fix this? A: The Appearance Integrity Report analyzes the document and finds any items or features that could possibly alter the […]
“Select a smart card device” error message when launching PDF Studio
Q: When I launch PDF Studio, an error message from Windows Security related to a smart card device displays. How can I resolve this issue? A: This message comes from the Windows digital ID store. You must have a digital ID set up to read from a smart card and there are some issues connecting to your smart […]
How to setup USB Smart Card Hardware PKCS11 signing on Mac
Q: I need to sign PDF documents with my USB Smart Card. Can I do that using PDF Studio on my Mac system? A: Yes, you can. Starting in PDF Studio 11.0.4, we allow users to sign a document using their USB Smart Card. You can see the setup below as a reference. In this example, we used […]
Signing PDFs with DOD CAC (Common Access Card) under Linux
Q: I work in the Air Force and have a requirement to digitally sign .pdf forms with my Common Access Card (CAC -> militaryID). Does the digital signing capabilities of your software PDF Studio interact with linux’s libcackey or your own libraries to enable digital signing of documents? Will my CAC work with your software? […]
How to setup USB Smart Card Hardware PKCS11 signing on Linux
Q: I need to sign PDF documents with my USB Smart Card. Can I do that using PDF Studio on my Linux system? A: Yes, you can. Starting in PDF Studio 10.1.0, we allow users to sign a document using their USB Smart Card. You can see the setup below as a reference. In this example, we […]
Ways to Sign a PDF Document on Windows, Mac and Linux with PDF Studio
Q: Is it possible to sign a PDF document using PDF Studio? A: Yes, PDF Studio offers multiple ways to sign PDF documents. Apply an Official Digital Signature (Pro Only) – This method is the most secure and accepted form of signature. It requires a pass worded digital certificate to be created prior to being […]
Multiple digital signatures on a PDF document
The PDF format was not designed to support multiple signatures. Advanced PDF viewers perform a trick when validating multiple signatures: they analyze the content that was added to see what was added after the first signature. If only a second signature was added, they show the first signature as valid. PDF Studio version 9 and […]