Fix Cannot Digitally Sign PDF with DoD Certificate on macOS Catalina
Question details
The user is unable to apply a digital signature to PDF documents using a DoD certificate after updating their Mac operating system to Catalina.
- Product
- PDF Readers
- Device & OS
- macOS Catalina
- Scenario
- Attempting to authenticate and sign a PDF using a DoD smart card or digital certificate on a recently updated macOS environment.
- Observed behavior
- The digital signature fails to apply, or the PDF software does not recognize the DoD certificate because the existing middleware and drivers are incompatible with the new OS.
Ensure your smart card reader is securely connected to your Mac and verify that you have administrative privileges to install new system drivers and middleware.
Update PDF Software and Smart Card Middleware
macOS Catalina dropped support for 32-bit applications and requires specific 64-bit drivers. Updating your PDF application and certificate middleware resolves these compatibility errors.
To properly read a DoD certificate on macOS Catalina, your PDF reader, smart-card drivers, and security plug-ins must all be 64-bit compatible. Older versions will fail to recognize the certificate.
Open your PDF reader, navigate to the Help menu, and select 'Check for Updates'. Ensure you are running a version specifically patched for macOS Catalina compatibility.
Contact your IT administrator or visit your certificate provider's portal to download the latest Catalina-compatible DoD certificate middleware and smart-card drivers.
Install the downloaded 64-bit middleware packages. Once the installation is complete, restart your Mac to ensure all background services load correctly.
Open the 'Keychain Access' app on your Mac. Insert your smart card and check if your DoD certificates populate in the Keychains list. If they do, configure your PDF software to use the correct digital ID.
Temporarily Downgrade to a Previous macOS Version
If updated middleware for your DoD certificate is not yet available from your IT department and you urgently need to sign documents, reverting your operating system is a viable workaround.
Digitally Sign PDFs Seamlessly with WPS Office
If you are experiencing continuous issues with your current PDF software, WPS Office provides a lightweight, reliable alternative. WPS PDF includes built-in tools for viewing, editing, and securely signing documents with digital IDs, ensuring your workflows remain uninterrupted across Mac and Windows devices.
- 1. Open your PDF file: Launch WPS Office and open the PDF document that requires your digital signature.
- 2. Navigate to the Protect tab: Click on the 'Protect' tab located in the top menu ribbon to access security features.
- 3. Select Sign Document: Click the 'Sign Document' or 'Digital Signature' button to initiate the signing process.
- 4. Apply your digital ID: Select your existing DoD certificate or digital ID from the list, draw your signature box, and apply it to the document.
Frequently Asked Questions
Why did my DoD certificate stop working after the macOS Catalina upgrade?
macOS Catalina removed all support for 32-bit applications and introduced stricter security protocols. Older smart card drivers and certificate middleware were likely 32-bit and must be updated to 64-bit, Catalina-compatible versions to function.
How do I check if my Mac recognizes my DoD smart card?
Open the 'Keychain Access' application on your Mac (found in Applications > Utilities). Insert your smart card into the reader. If the drivers are correctly installed, your DoD certificates will appear in the left-hand Keychains list.
Where can I get updated DoD certificate middleware for my Mac?
You should contact your organization's IT support team or visit the official DoD Cyber Exchange portal to download the most recent, macOS-compatible smart card drivers and middleware packages.
Will Acrobat automatically detect my new middleware?
Not always. After updating your middleware, you may need to go into Acrobat's Preferences > Signatures > Identities & Trusted Certificates, and manually point the application to the new PKCS#11 module or smart card driver file.
