Opening PDFs via double-click on DFS shares on Windows 10 does not work if Reader is already running

Hi,

As Amal suggested try updating, if that update didn't work , Just today another optional update was released : 

https://www.adobe.com/devnet-docs/acrobatetk/tools/ReleaseNotesDC/index.html

Some known issues were addressed, specifically:

Sandbox Problem: Acces

•  Denied error when trying to open PDF file from symbolic link via UNC path. [3844582]

See if this actually finally resolves this problem.

Hi,

NEW UPDATE WITH ASSUMED CORRECTIVE ACTIONS

Please refere to this thread: https://community.adobe.com/t5/acrobat-reader/can-only-open-1-pdf-at-a-time-from-dfs-server/m-p/10889532?page=2#M62593 

Hi,

I am going to post here the same info that I shared in a similar thread.

After much reading, I thinks the following references might be useful.

It seems like the DFS is preventing access to the  namespace when a client tries to hit a folder target with Acrobat in protected mode .

Verify if when  you add the absolute path for a priviledged location ,   

that the  namespace is not configured to issue referrals with the "insite" option.

See here  for troubleshooting: https://support.microsoft.com/en-us/help/975440/how-to-troubleshoot-distributed-file-system-namespace-access-failures 

Enable the cross domain troubleshooting log  in Reader / Acrobat and confirm if the messages that you get are not suggesting to "allow any" type of access which is the least restricted access policy, which would also defeat the purpose of using Enhanced Security and  Protected Mode .

See here too: https://www.adobe.com/devnet-docs/acrobatetk/tools/AppSec/xdomain.html#policy-file-configuration  

See here : https://helpx.adobe.com/acrobat/using/enhanced-security-setting-pdfs.html#bypass_enhanced_security_restrictions 

Since this seems to be not entirely related to Adobe Reader/Acrobat, there are a few more things that need to  be observed:

• Review on namespacing: https://docs.microsoft.com/en-us/windows/win32/fileio/naming-a-file 
• Review on how DFS works: https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2003/cc782417(v=ws.10)?redirectedfrom=MSDN 

• targetting you r applications for windows:  https://docs.microsoft.com/en-us/windows/win32/sysinfo/targeting-your-application-at-windows-8-1 
• How to configure fully qualified domains in referrals: https://support.microsoft.com/en-us/help/244380/how-to-configure-dfs-to-use-fully-qualified-domain-names-in-referrals 
• Configuring indicators in MS Windows Defender  Advanced Threat Protection https://docs.microsoft.com/en-us/windows/security/threat-protection/microsoft-defender-atp/manage-indicators 
• Configuring Defender AntiVirus exclusions:https://docs.microsoft.com/en-us/windows/security/threat-protection/windows-defender-antivirus/configure-server-exclusions-windows-defender-antivirus#opt-out-of-automatic-exclusions 
• Controlled Folder Access: https://docs.microsoft.com/en-us/windows/security/threat-protection/microsoft-defender-atp/enable-controlled-folders 
• Turning off scaning of DFS files: https://support.microsoft.com/en-us/help/822158/virus-scanning-recommendations-for-enterprise-computers-that-are-runni 
• Enhanced Security: https://www.adobe.com/devnet-docs/acrobatetk/tools/AppSec/enhanced.html#trust-overrides 
• Trusting documents with valid certification:https://helpx.adobe.com/reader/using/protected-mode-windows.html  
• Bypassing protected view restrictions: https://helpx.adobe.com/acrobat/using/protected-view-feature-pdfs-windows.html 
• See Application Security Guide in Troubleshooting Protected View: https://helpx.adobe.com/acrobat/kb/protected-mode-troubleshooting-reader.html  and see Application security libraries customization section in the Application Security Guide.
• Sandboxing : https://www.adobe.com/devnet-docs/acrobatetk/tools/AppSec/index.html 
• Desired Access and Shared Access to enable opening of shared files using  nNtCreateFile: https://docs.microsoft.com/en-us/windows/win32/api/winternl/nf-winternl-ntcreatefile  
• Operating system version API helper function: https://docs.microsoft.com/en-us/windows/win32/sysinfo/operating-system-version 
• Adding users to an encrypted file: https://docs.microsoft.com/en-us/windows/win32/fileio/adding-users-to-an-encrypted-file 
• See Workflow section -Actions for Shared Folders : https://www.adobe.com/devnet-docs/acrobatetk/tools/PrefRef/Windows/index.html 
• Creating file functions: https://docs.microsoft.com/en-us/windows/win32/api/fileapi/nf-fileapi-createfilea  
• Access based enumeration: https://docs.microsoft.com/en-us/windows-server/storage/dfs-namespaces/enable-access-based-enumeration-on-a-namespace  and using inherited permissions on access bases enumeration: https://docs.microsoft.com/en-us/previous-versions/windows/it-pro/windows-server-2008-R2-and-2008/dd834874(v=ws.11)?redirectedfrom=MSDN 

I hope these references help.

We have the same problem. We already sent over some process monitor log files months ago. It seems that there isn't a simple solution for this. See the other threads as well:

https://community.adobe.com/t5/acrobat-reader/can-only-open-1-pdf-at-a-time-from-dfs-server/td-p/10567535

https://community.adobe.com/t5/acrobat-reader/open-two-pdfs-from-dfs-server-2019/td-p/10332133

Since disabling protected mode isn't really a solution for us, we will switch to other software till this is fixed.

Just tested version 19.021.20056. Unfortunately not fixed yet.

I have sent the procmon logfiles to Amal. Hopefully this will help with the analysis.

(Problem exists since DFS is running on Windows Server 2019)

Problem still exists in Version 2019.021.20049

DFS Share on Windows Server 2019

Clients Windows 10 1809

We are experiencing the exact same issue.  It has been frankly maddening, particularly to see similar threads dating back to 2015 indicating similar problems.

Disabling Protected Mode is not an option.

Hi There,

Thanks for highlighting this issue. Could you please share the process monitor log files for the affected machine. Please download the process monitor tool using the link https://docs.microsoft.com/en-us/sysinternals/downloads/procmon run the application and share the log files with us so that we can assist you better.

Also could you please share some sample files with us in private message for testing. Please click on the message icon on the top right corner to send the private message.

Regards

Amal