Signing PDF document asks for "Smart Card"

[just-ero]

I want to sign a PDF document with my digital certificate (.p12). When I click "Sign", Windows (11 Pro) prompts me to connect a smart card. I have no idea what that is and do not own one. Signing worked fine before I enabled Windows Hello on my device. Disabling it and restarting the app does not change the behavior. The certificate works in other apps and all information is up to date.

I would like to simply sign the document with my certificate just like before.

[Tariq Ahmad Dar]

Hi there,

Thanks for bringing this up. I know it can be confusing when Acrobat suddenly prompts for a smart card or digital ID when trying to sign a document.

Why You’re Seeing the Smart Card Prompt:

Acrobat is likely set to use a certificate-based digital signature, and it’s trying to access a hardware-based digital ID, such as a smart card or USB token, that it expects to be connected to your machine.

This happens when:

• A digital signature field is configured to require a certificate.

• Acrobat detects that your system has previously used a smart card or token-based certificate (even if it’s no longer connected).

• Or, the default digital ID in Acrobat preferences is pointing to a certificate that requires smart card authentication.

Alternatively:

If you don’t want to use a smart card or digital certificate, and just need to apply a simple signature or type/draw a signature, follow these steps:

1. Use “Fill & Sign” instead of a signature field:

• Open the PDF in Acrobat.

• Go to Tools > Fill & Sign.

• Use the Sign option to type, draw, or insert an image of your signature — no smart card needed!

2. Clear saved digital IDs (if unwanted):

• Go to Edit > Preferences > Signatures.

• Under Identities & Trusted Certificates, click More…

• Review and remove any old or unused certificates that reference smart cards.

3. Check the signature field type:

• If the PDF was created by someone else and contains a certificate-based signature field, you may need to ask them to provide a version that allows for Fill & Sign instead.

~Tariq

[just-ero]

Thanks Tariq. Unfortunately I couldn't find a satisfying solution in your answer.

I do want to use my certificate. I simply do not want to be prompted with a smart card pop-up.

The certificate does not require smart card authentication.

I have previously only connected a physical security key (YubiKey). I don't know whether Acrobat considers that a "smart card" or "token-based certificate". In any case; inserting the YubiKey does not change anything.

[just-ero]

Hello again, Tariq.

I want to correct my previous comment. Inserting the YubiKey does work. However, once I try signing (I can now get past the Smart Card prompt), I'm met with an error:

Error encountered while signing:

The Windows Cryptographic Service Provider reported an error:
One or more of the supplied parameters could not be properly interpreted.
Error Code: 2148532228 (0x80100004)

What might be causing this?