The Adobe Acrobat PDF (Portable Document Format) software throws out an “Acrobat failed to connect to a DDE server” error message for some users.

That error message can pop up when users try to open PDFs or merge documents within Adobe Acrobat.

Consequently, users can’t open a PDF or merge documents in Acrobat when the issue arises. This is how users can fix the “Acrobat failed to connect to a DDE server” error in Windows 10.

How can I fix Acrobat’s DDE server error:

1. Update the Acrobat Software

The DDE server error will more likely arise for older versions of Adobe Acrobat. Adobe might have released an update that fixes the DDE server issue. Thus, updating Acrobat to the latest version might fix the issue for some users.

Users can update the software by clicking Help > Check for Updates in Acrobat. That will open the Updater window that installs updates. Alternatively, users can uninstall the software and reinstall it as follows:

  1. Right-click the Start menu and select Run.
  2. Enter ‘appwiz.cpl’ in the text box and click OK.
  3. Select Adobe Acrobat and click Uninstall.
  4. Click the Yes button to confirm.
  5. Restart Windows after uninstalling Adobe Acrobat.
  6. Next, open the Adobe Acrobat page in a browser.


You can’t open Control Panel? Take a look at this step-by-step guide to find a solution.


2. Turn Off Antivirus Software

Some third-party antivirus utilities might flag Adobe Acrobat when users try to merge PDFs. So, turning off antivirus software is another potential resolution for the DDE error.

Users can usually select to temporarily disable antivirus software by right-clicking their system tray icons and selecting a disable, exit, pause, or turn off the option.

If there isn’t a disable option on the software’s context menu, open the utility’s primary window and look for a turn off option on its settings tab.


Do you want to check if your firewall is blocking Adobe Acrobat? Follow the simple steps from this guide to find out.


3. Edit the Registry

This registry edit is one of Adobe’s official resolutions for the DDE error. The edit requires that users modify an application key for Acrobat. Follow the guidelines below to edit the registry.

  1. First, press the Windows key + X hotkey.
  2. Select Run to open that accessory.
  3. Input ‘regedit’ in the text box and press Enter to open the Registry Editor.
  4. Enter this registry path in the address bar: Computer\HKEY_CLASSES_ROOT\acrobat\shell\open\ddeexec\application.
  5. Select the application key on the left of the Registry Editor’s window.
  6. Double-click Default to open the Edit String window shown directly below.
  7. Then delete the current ‘AcroviewA18’ or ‘AcroviewA19’ text in the Value data box.
  8. Enter ‘AcroviewR18’ in the Value data box if the original value was ‘AcroviewA18.’ Note that the A and R values depend on the version installed, so some users might need to enter ‘AcroviewR19.’
  9. Then click the OK button.
  10. Restart Windows after editing the registry.

If you can’t edit your Windows 10‘s registry, read this handy guide and find the easiest solutions to the issue.


Can’t access the Registry Editor? Things aren’t as scary as they seem. Check out this guide and solve the issue quickly.


4. Repair Acrobat

  1. Some users have fixed the DDE server error by repairing Acrobat’s installation. To do that, open Run.
  2. Enter ‘appwiz.cpl’ in Run and press Return.
  3. Select the Adobe Acrobat software.
  4. Press the Change button to open the window in the image directly below.
  5. Select the Repair installation errors in the program option.
  6. Press the Next button.
  7. Click Finish when the repair installation process is done.

If you encounter an error like There was a problem with Adobe Acrobat Reader, fix it with the help of this guide.


5. Turn Off Protected Mode at Startup

Deselecting the Protected Mode at startup and Enhanced Security settings is another resolution that has fixed the DDE server error some Acrobat users. To do that, click Edit > Preferences in Acrobat to open the window in the shot directly below.

  1. Click Security (Enhanced) on the left of that window to open the options shown below.
  2. Deselect the Enable Protected Mode at Startup option.
  3. Deselect the Enable Enhanced Security option.
  4. Close the Preferences window and Adobe Acrobat.
  5. Thereafter, open Adobe to see if that resolution has fixed the DDE server error.

Those are resolutions that have fixed the DDE server error for Adobe Acrobat users. So, they’ll probably resolve the error. If further fixes are still needed, however, Acrobat users can log in to adobe.com to open a support case.

If you have any more suggestions or questions, don’t hesitate to leave them in the comments below and will surely take a look.

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