Hello,I’m using Adobe Acrobat Reader Version 2026.002.21901 on macOS and need to attach the PKCS#11 module for Romania’s electronic identity card (CEI), issued by the Romanian Ministry of Internal Affairs.In Preferences → Signatures → Identities & Trusted Certificates → More → PKCS#11 Modules and Tokens, the “Attach Module” button is visible but permanently disabled (greyed out).I have already tried: Disabling Enhanced Security; Fully quitting and reopening Acrobat Reader; Running Acrobat Reader with Rosetta; Confirming that the CEI middleware (IDPLUGMANAGER for macOS) is installed. The card reader and CEI are required for signing PDF documents. Since Acrobat does not allow the PKCS#11 library to be attached, I cannot use the digital certificate stored on the CEI.Could you please confirm whether this is a known limitation or bug in the current macOS version of Acrobat Reader, and provide a supported workaround?Thank you.

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“Attach Module” button disabled on macOS — Romanian electronic ID card (CEI) PKCS#11

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Hello,

I’m using Adobe Acrobat Reader Version 2026.002.21901 on macOS and need to attach the PKCS#11 module for Romania’s electronic identity card (CEI), issued by the Romanian Ministry of Internal Affairs.

In Preferences → Signatures → Identities & Trusted Certificates → More → PKCS#11 Modules and Tokens, the “Attach Module” button is visible but permanently disabled (greyed out).

I have already tried:

Disabling Enhanced Security;
Fully quitting and reopening Acrobat Reader;
Running Acrobat Reader with Rosetta;
Confirming that the CEI middleware (IDPLUGMANAGER for macOS) is installed.

The card reader and CEI are required for signing PDF documents. Since Acrobat does not allow the PKCS#11 library to be attached, I cannot use the digital certificate stored on the CEI.

Could you please confirm whether this is a known limitation or bug in the current macOS version of Acrobat Reader, and provide a supported workaround?

Thank you.

V

Vivacious_Coral5c9a

Participant

Confirming the downgrade workaround also works for Indian DSC USB tokens (Hypersecu HYP2003 / ePass2003-type, Capricorn individual DSC).

My setup:
- MacBook with Apple A18 Pro chip
- Acrobat Reader 2026.002.21931 (Continuous Release)
- Hypersecu HYP2003 token, EnterSafe / Hypersecu PKI Manager middleware
- PKCS#11 library: /usr/local/lib/libcastle_v2.1.0.0.dylib (universal binary, x86_64 + arm64)

Problem: the token and certificate showed correctly in the Hypersecu PKI Manager, but Acrobat said "could not find any new digital IDs". Under Preferences > Signatures > Identities & Trusted Certificates > More > PKCS#11 Modules and Tokens, the Attach Module, Detach Module and Refresh buttons were all greyed out. Security (Enhanced) had no "Enable Protected Mode at startup" option to untick, so the earlier workaround wasn't available.

What fixed it:
1. Downloaded Acrobat Reader 2024.004.20272 for Mac (link posted earlier in this thread).
2. Quit Acrobat completely. If the uninstaller says the app is still running, use Cmd+Option+Esc to Force Quit Acrobat, and close any Adobe processes in Activity Monitor.
3. Uninstalled the 2026 version using Applications > Adobe Acrobat DC > Acrobat Uninstaller.
4. Installed the 2024.004.20272 version.
5. Preferences > Security (Enhanced) > unticked "Enable Enhanced Security", then quit with Cmd+Q.
6. Applications > right-click Acrobat > Get Info > ticked "Open using Rosetta".
7. With the token plugged in and the token manager app closed, opened Acrobat > Preferences > Signatures > Identities & Trusted Certificates > More > PKCS#11 Modules and Tokens > Attach Module, and entered /usr/local/lib/libcastle_v2.1.0.0.dylib
8. Selected the token, clicked Login, entered the token PIN. The signing certificate appeared.
9. Signed the PDF via Use a certificate > Digitally sign.

Tip: to find your token's library path, run this in Terminal:
ls /usr/local/lib/ | grep -iE "castle|epass|es_|hyper"

Caution: decline automatic updates for now, or the bug comes back. The older version lacks recent security fixes, so avoid opening PDFs from unknown senders and update once Adobe fixes this.

Adobe team: please restore PKCS#11 Attach Module support in the current Mac build, as many Indian CAs, companies and professionals rely on USB DSC tokens for statutory filings and reports.

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Anand Sri Bhattacharya

Community Manager

Thanks for sharing the detailed information @Vivacious_Coral5c9a

You can use the Acrobat Wish form to file a feature request with the product team about adding new features: https://acrobat.uservoice.com/

Regards,

Anand Sri.

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motivated_Dewdrop8fa1

Participant

My system details:

MacBook Pro 14-inch (2025)
Apple M5 Pro, 24 GB
macOS Tahoe 26.6.2
Acrobat Reader version: 26.2.21901.0

I have already tried:

Disabling Enhanced Security (Preference > Security (Enhanced) > Unchecked “Enabled Enhanced Security”
Fully quitting and reopening Acrobat Reader; (Cmd +Q)
Running Acrobat Reader with Rosetta (Adobe Acrobat.app > Right Click (Get Info) > Checked “Open using Rosetta”
I tried searching the 24.4.20272.0 version but did not find copy of it.

Guys I am stuck on this simple thing since days but no solution so far. Pls patch the version.

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A

Alexander28319393e0bg

Participating Frequently

Make sure that you uncheck “Enable Protected Mode at startup (Preview)” in the Security (Enhanced) settings.

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motivated_Dewdrop8fa1

Participant

Ok. Downgrading to “2024.004.20272.0” worked here are the steps to help others

I am working with the Adobe Reader to sign a document with Individual DSC from https://www.vsign.in/ in a USB key.

Download the older version “https://get.adobe.com/reader/download?os=Mac+OS+11.0.0&name=Reader+2024.004.20272+for+Mac&lang=en&nativeOs=Mac+OS+11.0.0&accepted=&declined=&preInstalled=&site=landing#”
Completely uninstall the existing 2026 version. Use “Acrobat Uninstaller” which is available in the same “Adobe Acrobat DC” application section.
Install the newer version
Preference > Security (Enhanced) > Unchecked “Enabled Enhanced Security
Cmd + Q
Adobe Acrobat.app > Right Click (Get Info) > Checked “Open using Rosetta”
Open the Adobe Reader
Preferences > Signatures > Identities & Trusted Certificates > more … > PKCS#11 Modules & Tokens > Attach Module > Library Path “/usr/local/lib/libcryptoida_pkcs11.dylib” this is your library path to let adobe read from the USB device.
1. the libcryptoida_pkcs11.dylib may differ from device to device so consider it as *.dylib path > Click Ok in the library path dialog
2. “Longmain PKCS#11 Library” appears now
3. Click add id + > if USB key is password protected, enter password
4. DONE
Locate the place in the document to sign, click on it.
Follow the prompts that asks to load signature from the attached device
Once sign is setup it will sign the clicked box.

Thank you.

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Anand Sri Bhattacharya

Community Manager

Hello All,

Thanks for your patience and cooperation on this.

Please note that currently, attaching PKCS#11 modules is disabled when Acrobat/Reader is running in Protected Mode.

To attach the required PKCS#11 modules, please follow these steps:
1.   Go to Preferences > Security (Enhanced).
2.   Uncheck Enable Protected Mode at startup.
3.   Restart Acrobat/Reader.
4.   Go to PKCS#11 Modules and Tokens and attach the required module.

Please note that disabling Enhanced Security itself does not disable Protected Mode. The Enable Protected Mode at startup option must specifically be unchecked.

Please use this approach, as attaching PKCS#11 modules is currently disabled while Protected Mode is enabled.

Let us know how it goes and reach out if you need any assistance.

Regards,

Anand Sri.

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A

Alexander28319393e0bg

Participating Frequently

The option to disable Protect Mode at Startup is no longer preset with the latest update. That was a workaround in previous versions.

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Anand Sri Bhattacharya

Community Manager

Hi @Alexander28319393e0bg

Thanks for sharing the screenshot. Could you please confirm the version of Acrobat installed? Check from Acrobat > Help > About Adobe Acrobat.

Regards,

Anand Sri.

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Anand Sri Bhattacharya

Community Manager

Hello!

I have reported this to the product team for further investigation, and I may reach out if we need any specific information for the investigation.

Thanks for your cooperation on this.

Regards,

Anand Sri.

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G

graceful_doerce6a

Participant

same problem here, Acrobat Reader 26.2.21901 shows the Attach Module button under PKCS#11 Modules and Tokens as permanently disabled/greyed out.

MacBook Pro, Apple M1 Pro, arm64

PKCS#11 library: /usr/local/lib/libeTPkcs11.dylib

Library is a universal binary with both x86_64 and arm64

The token and PKCS#11 module work correctly in Firefox

Disabling Protected Mode / Enhanced Security and restarting Acrobat does not enable the button

Acrobat preferences already contain the PKCS#11 module path under Security > ASPKI > Adobe_P11CredentialProvider > Modules

looks like an acrobat reader regression

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G

graceful_doerce6a

Participant

ended up uninstalling it and installing an older version (Build: 24.4.20272.0) that did the job …

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BaniVerma

Community Manager

Hi @graceful_doerce6a,

Thank you for adding your details here, especially for confirming that the PKCS#11 module path already appears correctly under Security > ASPKI > Adobe_P11CredentialProvider > Modules in preferences, yet the Attach Module button remains disabled. That's a useful data point alongside what others have reported in this thread.

This looks consistent with what others on Apple Silicon Macs have described in this thread with recent Acrobat Reader builds, and disabling Enhanced Security not resolving it lines up with what we've seen reported here as well.

Thanks also for sharing that reinstalling with the older build (24.4.20272.0) worked around it for you; that's helpful for others hitting this in the meantime. That said, we'd treat it as a temporary workaround rather than something to stay on long-term, since Adobe recommends keeping Acrobat updated to the latest version for security fixes.

Thanks for the detail, it's genuinely helpful.

Regards,
^BS

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A

Alexander28319393e0bg

Participating Frequently

Seeing the same issue with the same troubleshooting steps on a Mac in our fleet as well.

MacBook Air 15-inch M5
macOS 26.6.2
DigiCert signing token with SafeNet Authentication Client 10.9.2499 (GA).
- Note: the token and signing certificate are viewable perfectly fine here.
Completed the first ever install of Adobe Acrobat DC (26.002.21901) on this computer today with the latest version.
Attach button grayed out through all troubleshooting steps (same steps as the original poster).

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Anand Sri Bhattacharya

Community Manager

Hello @Alexander28319393e0bg

I hope you are doing well, and thanks for sharing the details. Sorry for the trouble you had.

Please allow us some time to get this checked, and we will get back to you with an update.

Thanks for your cooperation on this, and please reach out if you need any assistance.

Regards,

Anand Sri.

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C

Colorful_calmness8fdf

Participant

Hello everyone!

@albert_3778, thank you very much for sharing this issue.

I work on the technical side of a company that provides digital signature certificates, and we are currently seeing the same issue with several new customers who use Macs.

Hopefully, we can find a solution or clarify whether there is something we may be missing on our side.

In previous versions of Adobe Acrobat, it was enough to disable “Enable Enhanced Security” and restart Acrobat. After restarting, the “Attach Module” button became available and we were able to attach the PKCS#11 module.

With the current version, however, this no longer works. Even after disabling “Enable Enhanced Security” and fully restarting Acrobat, the “Attach Module” button remains disabled.

We would greatly appreciate any guidance or clarification from Adobe regarding this behavior.

Thank you in advance for your help!

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Amal Jaiswal

Community Manager

Hi @albert_3778 ,

Hope you are doing well, and thanks for the detailed screenshots, that's very helpful.

Please try the steps below and see if that works for you:

Go to Preferences > Security (Enhanced)
Make sure "Enable Enhanced Security" is unchecked (For testing only)
Note: Please turn on the security after testing to avoid any security risks
This part is important and often missed: fully quit Acrobat afterward (Cmd+Q, or right-click the Dock icon and choose Quit, not just closing the window), then reopen it
Go back to Preferences > Signatures > Identities & Trusted Certificates > PKCS#11 Modules and Tokens, and check whether Attach Module is now clickable

Your first screenshot shows that the checkbox looks unchecked already, but if you haven't done a full quit-and-reopen since unchecking it, that would explain why it's still grayed out; the setting doesn't apply live.

If you've already done a full restart and it's still disabled, a couple of follow-up questions: what macOS version are you on, and is this an Apple Silicon or Intel Mac? If Apple Silicon, one other workaround that's helped in similar cases is running Acrobat under Rosetta.

Let us know if the full quit-and-reopen after unchecking Enhanced Security resolves it.

Regards
Amal

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A

albert_3778Author

Participant

Hi Amal,

Thank you for the reply.

I have already unchecked “Enable Enhanced Security” and fully quit Acrobat with Cmd+Q, then reopened it. The “Attach Module” button is still disabled.

I also tried running Acrobat under Rosetta, but the issue remains.

My system details:

MacBook Pro 14-inch (2021)
Apple M1 Pro
macOS Tahoe 26.6.2
Acrobat Reader version: 2026.002.21901

I need to attach the PKCS#11 module for the Romanian electronic identity card (CEI), using the official IDPLUGMANAGER middleware.

Could you please advise whether this is a known limitation with Acrobat Reader on Apple Silicon/macOS Tahoe, or whether there is another setting or supported workaround to enable “Attach Module”?

Also, is there any plan to support Romania’s electronic identity card (CEI) directly in Acrobat Reader on macOS, without manually attaching a PKCS#11 module? The official CEI middleware is available for macOS, but the disabled “Attach Module” button prevents users from accessing the certificate stored on the card.

Regards,
Albert

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