Microsoft Edge Chromium is set as the default PDF reader to open and view PDF files in Windows 10. So, whenever I attempt to open any PDF file in Windows 10, it automatically gets opened in Edge browser, although my preferred choice is Acrobat Reader. Moreover, when I try to change the settings, the browser hijacks it and resorts to its old behavior again. While many would not oppose this move, I believe, it’s not intended for everyone. So, here’s how you can stop Edge from changing the PDF viewer association.
Stop Edge from hijacking PDF/HTML associations
The change is observed to be triggered by a reset of File Association for a file type, which restores Windows 10 defaults. But, why do PDF FileAssociations get reset every time a user restarts his PC.
Well, The feature team for FileAssociation explains that its protection mechanism in Windows 10 prevents direct changes to the UserChoice area of the registry for each file type. As such, when no FileAssociation is configured in the registry or if an application makes the hash void by incorrectly writing to the UserChoice registry key to set associations, a reset of FileAssociation for that file type gets triggered, restoring default status. Hence, we need to edit a registry entry.
Here is the solution to the PDF/HTML file type being continually reassigned to Microsoft Edge browser.
Microsoft Edge Chromium
if you find that PDF files open automatically in the Edge browser without downloading them, you’ll need to tweak a setting. It will prevent the Edge browser from being the default PDF reader. Here’s how it’s done!
Open Microsoft Edge browser.
Click Settings and more from the upper-right corner.
Select Settings and go to Cookies and site permissions as shown in the image above.
Switch to the right side and scroll down to the All permission section.
Under it, locate the PDF documents entry.
Now, toggle the switch for the Always download PDF files option to the Off position.
When done, close the browser and re-launch it.
Microsoft Edge Legacy
Open the ‘Run’ dialog box, type ‘Regedit’ and hit ‘Ok’ button. Next, navigate to the following key –
Please note that, under the key that starts with Microsoft.MicrosoftEdge the address could be different in some versions of Windows.
For instance, in my case it was-
When found, simply expand this key and others under it. Then, choose FileAssociations and look at the entries provided in the right corner of the screen.
Observe closely the Data string displayed for the .pdf name.
At the time of this writing, the string is this, but it may be different in your case-
Right-click on the above entry and select the Rename option from the menu displayed.
After that, add the underscore character to the end of the name and press Enter to save the new name.
When done, navigate to Control Panel and open the Default Programs applet to configure the change, i.e., choosing a different application as the default application for the PDF files.
From now on, Edge should not reinstall itself as the default application.
Should you wish to change this setting to original and restore the earlier experience, simply remove the underscore character from the name of the key-
If Windows does not allow you to edit the Registry key, you may need to run regedit as admin and take ownership of the Registry key.
Hope this helps!