How to Fix Alphanumeric Characters in Adobe Acrobat's Sign As Field
Question details
The user is encountering unexpected random alphanumeric characters in the "Sign As" dropdown field when attempting to sign a PDF document.
- Product
- Adobe Acrobat
- Device & OS
- not provided
- Scenario
- Applying a digital signature to a PDF document using a self-signed certificate or smart card.
- Observed behavior
- Instead of displaying the correct certificate name, the "Sign As" field shows a string of alphanumeric characters, preventing proper signature application and indicating a corrupted digital ID.
Verify whether your digital signature is based on a self-signed certificate stored on your computer or a physical smart card, as the troubleshooting steps differ for hardware tokens.
Remove Corrupted Digital ID and Recreate a New Self-Signed Certificate
Deleting the problematic certificate from Acrobat's trusted identities and generating a fresh one is the most effective way to resolve display and corruption issues in the "Sign As" field.
Unexpected characters in the signature field usually indicate that the digital ID file (.pfx or .p12) has become corrupted or that Acrobat is failing to read its metadata correctly.
If you are using a smart card rather than a self-signed certificate, do not attempt to delete the ID. Instead, try reconnecting the card reader and updating its drivers.
Open Adobe Acrobat, navigate to 'Edit' > 'Preferences' (or Acrobat > Preferences on Mac), select 'Signatures' from the left pane, and click the 'More' button under 'Identities & Trusted Certificates'.
Expand the 'Digital IDs' section on the left, select 'Digital ID Files', locate the corrupted self-signed certificate displaying alphanumeric characters, and click 'Detach File' or 'Remove ID'.
Click the 'Add ID' button at the top, select 'A new digital ID I want to create now', and click 'Next'.
Fill in your Name, Organizational Unit, Organization Name, and Email Address. Ensure the 'Key Algorithm' is set to 2048-bit RSA for standard security, then click 'Next'.
Set a strong password to protect the new digital ID and save it. Open your PDF document, click to sign, and verify that the new certificate name appears correctly in the 'Sign As' dropdown menu.
Sign PDF Documents Securely with WPS Office
If you are struggling with complex certificate configurations in Adobe Acrobat, WPS Office provides a streamlined, intuitive interface for securely adding digital and electronic signatures to your PDF documents.
- 1. Open your PDF Document: Launch WPS Office and open the PDF file you need to sign.
- 2. Access the Signature Tool: Navigate to the 'Fill & Sign' or 'Protect' tab on the top ribbon and click on 'Sign'.
- 3. Create Your Signature: Click 'Create Signature'. You can type your name, draw your signature, or import an image of your physical signature.
- 4. Place and Save: Click anywhere on the document to place the signature, adjust its size if necessary, and save your PDF.
Frequently Asked Questions
Why does my Adobe Acrobat digital signature show random letters and numbers?
This typically occurs when the self-signed digital certificate file (.pfx or .p12) becomes corrupted, or Acrobat loses proper access to the file's metadata, causing it to display the internal ID string instead of your name.
Can I fix the alphanumeric character error if I am using a smart card?
If you use a hardware smart card, the issue often stems from a communication error rather than file corruption. Try reconnecting the card reader, updating your smart card middleware/drivers, or restarting your computer, as you cannot delete and recreate a smart card ID directly in Acrobat.
Where are Adobe Acrobat self-signed digital IDs stored on my computer?
On Windows, self-signed digital IDs are typically stored in the user profile directory, commonly located at C:\Users\[YourUsername]\AppData\Roaming\Adobe\Acrobat\.
Will I lose access to previously signed documents if I remove my corrupted digital ID?
No. Documents that were already signed, saved, and flattened with the old digital ID will remain signed and intact. However, you will need to use your newly generated ID for any future document signing.
