Acrobat DC Failed To Connect To A DDE Server Windows 10

Adobe makes of the most popular creator suite applications, which includes the likes of Photoshop and Lightroom for photo editing, Premiere Pro for video editing and Acrobat DC for viewing PDF documents. Although there is a developer team working constantly to continuously improve the software, there are occasional bugs that may end up throwing error messages at users.

One of the most common error messages that users receive while opening or merging PDFs is the ‘Acrobat failed to connect to a DDE server’ error. Users cannot open or merge PDFs when they get this error message. Here, I shall discuss what a DDE server is, and how you can solve the Acrobat DC failed to connect error.

What Is A DDE Server?

You must have at least heard once about a DDE server if you are familiar with computers or spend a lot of time around one. DDE stands for Dynamic Data Exchange, and it is actually a data exchange protocol.

DDE is a method of exchanging information in between applications that are installed on the Windows operating system. The concept of a DDE server has been around for quite a while, with the earliest example said to be data exchange between Word and Excel on Windows 2.0!

The ‘Acrobat failed to connect to a DDE server’ error is usually caused by the limitations in the connection between the DDE client and the server. The communications between the client (Adobe Acrobat) and the server (PLC and other drivers) usually have to pass through a software message routing mechanism in Windows.

This added route can make the connections slow at times.

How To Fix If Acrobat Failed To Connect To A DDE Server?

There can be many reasons that can cause the client software not to reach the DDE server. Here are some simple solutions that you can use to troubleshoot and solve the ‘Acrobat failed to connect’ error.

Solution 1: Update Adobe Acrobat

An outdated software is one of the most common causes of this error. It may have happened that Adobe may have silently pushed an update that you may have missed, or that you may have forgotten to update your applications. An older version of Adobe Acrobat Reader may be conflicting with your file and causing your ‘Adobe failed to connect to a DDE server’ error.

The latest security patch update of Adobe Acrobat reader should fix your errors. To update the reader:

1. Open Adobe Reader.
2. In the ribbon toolbar, click on the Help option.
3. Here, click on the Check for Updates… option.

4. If you missed any updates, the Update is available dialogue box will open.
5. Now, you need to follow the on-screen instructions to update the Adobe Acrobat reader.
6. Restart your PC following the update.

This should resolve your issue with Acrobat not being able to connect to DDE server in Windows 10.

Solution 2: Modify Registry To Update Acrobat Values

The Registry in Windows 10 contains all the configuration files and the application settings for the software installed on your computer. With every update, the registry keys are automatically updated. However, if you have not updated your application in a long time, or the registry values were not updated, there is a chance that you may get the ‘Acrobat failed to connect to a DDE server’ error.

To rectify this error, you need to update the registry keys manually. To do so, follow these steps:

1. Open a Run dialog by pressing Win + R.
2. Type regedit and press Enter to launch the Registry Editor console.
3. Navigate to the following location by pasting the path in the address bar of the Registry Editor:
   Computer\HKEY_CLASSES_ROOT\acrobat\shell\open\ddeexec\application
4. With the application key highlighted, check the value of the Default string key in the right pane.
5. Double click to modify the key.
6. Change the value data from AcroViewA18/A19 to AcroViewR18/R19
   Note: here, A19 and R19 refer to the version of Adobe Acrobat installed.

7. Close the Registry editor and restart your device.

Now, try opening the PDF using Adobe Acrobat and check if the error persists. You should be able to launch PDFs normally, or merge them as well.

Solution 3: Review Antivirus Blocks

Your antivirus sometimes prevents additional downloads over the internet, or blocks applications from accessing data over the internet. This can be the reason that Adobe fails to connect to the DDE server for your action.

Turn off the antivirus shields for a while, and then attempt to open or merge PDF files. This should solve your error, and you should be able to work on your PDFs normally.

Solution 4: Turn Off Protected Mode At Startup

Sandboxing refers to a protection technique used by developers to create a confined execution environment for running programs that may be harmful or cannot be trusted. If the PDF that you are trying to run invokes such security protocols, you may get such errors.

To remove this, you need to turn off protected mode at startup. Simply follow these steps for the same:

1. Open Adobe Acrobat reader on your computer.
2. In the ribbon toolbar, click on the Edit option.
3. Here, click on Preferences.
4. From the Categories menu in the left pane, select Security (Enhanced).
5. Under Sandbox Protections subsection, uncheck the box that is associated to Enable Protected Mode at startup.

This usually solves the ‘Adobe failed to connect to a DDE server’ error from the next time you open a PDF file on your system.

If this does not solve your error, you will have to repair the installation, as there might be something wrong with the core installation files themselves.

Solution 5: Reinstall Adobe Acrobat

Adobe has included an option that can help you repair the installation files of your Adobe programs. You can use this feature to check for any corrupt or broken installation files on your computer.

1. Open Adobe Reader.
2. In the ribbon toolbar, click on the Help option.
3. Select Repair Adobe Reader Installation from the revealed context menu.

4. Follow the on-screen instructions to repair the installation of Adobe Acrobat reader.

Note: If this fails, you need to uninstall the Adobe Acrobat reader from your computer, and then download the installer file again from the official website.

Reinstalling the adobe is a good way to solve any issues with the PDF reader, which was probably misbehaving because of any missing or corrupt components. You should be able to open the PDF file normally after reinstalling the Adobe Acrobat reader.

Conclusion

So there you have it. Now you know how to solve if you see the ‘Acrobat failed to connect to a DDE server’ error message using one or a combination of the solutions provided above. Did you find this useful? Comment below if you did, and to discuss further the same.