Acrobat Failed to Connect to a DDE Server (Complete Tutorial)
Acrobat Reader is Adobe’s free app for opening its proprietary PDF file format. If you need to create or edit a PDF, from Adobe’s suite you will need Acrobat DC. The program isn’t free, so you will need to purchase a standard subscription to use it or to find a third-party app for the job. But since a lot of users prefer to use Acrobat DC, we’re here to explain what you should do if Acrobat failed to connect to a DDE server — which is a common error.
Acrobat failed to connect to a DDE server
Acrobat is a feature-rich app that allows users to edit PDF files; you can view them, add/remove text, combine multiple files into one, remove a page from a file, add images, remove images, and more. As such, the ‘failed to connect to a DDE server’ error can appear when you;
- Open a file
- Combine multiple files into one PDF
- Open the Acrobat DC app
This error used to be quite common in 2011 and 2017 and was a known bug at the time. It was patched via an update to the Acrobat DC app but it will resurface now and then. The only difference is that Adobe doesn’t have the fix for it this time. Try the fixes below and the problem should go away.
1. Try a different PDF file
It’s possible that the PDF file you’re trying to open or combine with other files is the problem. Try opening a different file, or files, and see if the problem still appears. If it doesn’t, your files are likely the problem. If the problem persists, try another fix.
2. Relaunch the app
Close all instances of Acrobat DC and then open the app again.
- Tap the Win+R keyboard shortcut to open the Run box.
- In the Run box, enter the following and tap Enter.
Taskkill /IM acrobat.exe /f
- A Command Prompt window will appear and then disappear. Once it does, you can launch the app again.
3. Update Acrobat DC
While this error isn’t generally pervasive in a particular version of the app, updating it can help resolve the problem in some cases. If you’re able to open the app, follow these steps
- Open the Acrobat DC app.
- Go to Help>Check for Updates.
- Install an update if it’s available.
If you’re unable to open Acrobat DC, you’re going to have to uninstall the app and download and install it again.
- Open Control Panel.
- Go to Programs>Uninstall a Program.
- Select Adobe Acrobat DC, and click the Uninstall button at the top.
- Once the app has been uninstalled, download and install it again.
4. Repair Acrobat DC
Acrobat DC can run into problems and it has a built-in repair feature in case something breaks. If you’re able to open the app, follow these steps to repair it.
- Open Acrobat DC.
- Go to Help>Repair Installation.
- Allow the app to finish repairs, and relaunch it.
If you’re unable to run Acrobat DC without seeing the ‘failed to connect to a DDE server’ error, you can initiate a repair from the Control Panel.
- Open Control Panel.
- Go to Programs>Uninstall a Program.
- Select Adobe Acrobat DC from the list of installed apps.
- Click the Change button.
- In the window that opens, click Next, and then select the Repair option.
- Allow the app to be repaired and then open it.
5. Edit version number in registry
You may be seeing this error if you’ve updated Acrobat DC from an older version to a new one. The version may not have updated in the Windows registry and you will have to fix it manually. In order to do that, you need to find the version number of Acrobat DC.
Acrobat DC version number
If you’re able to open the Acrobat DC app, follow these steps to find the version number.
- Open Acrobat DC.
- Go to Help>About Adobe Acrobat DC Pro.
- In the window that opens, check the app’s version number.
If you’re unable to open the Acrobat DC app, follow these steps;
- Open the Control Panel.
- Go to Programs>Uninstall a program.
- Select Adobe Acrobat DC.
- Look in the Version column to find the app’s version number.
Edit Windows Registry
- Tap the Win+R keyboard shortcut to open the Run box.
- In the Run box, enter ‘regedit’, and tap Enter.
- In the registry editor, navigate to the following key.
HKEY_CLASSES_ROOT\acrobat\shell\open\ddeexec\application
- Double-click the Default value.
- Make sure the number corresponds to the app version. For example, if you’re running version 20.xxx of Adobe Acrobat DC, the value data box should read “AcroViewA20”. Change only the number at the end. The string that proceeds the number may differ and that isn’t anything to worry about so long as the version number matches.
- Restart Acrobat DC and the error will be resolved.
Conclusion
The ‘failed to connect to a DDE server’ error is a bit confusing because the message leads users to think there’s a problem with an online service that Acrobat DC is trying to access.
It is actually a problem with the app itself but not one that users can troubleshoot directly by changing a setting or two.
Instead the app will either have to be installed fresh, repaired, or manually fixed from the registry.
