Set the default pdf viewer app in Windows 10 Registry?

Question

------------------------------------Update------------------------------ I tried the solution in the first answer, however, since there are Hash under user choice, it won't allow me to edit the value to foxitreader.document

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I installed a PDF viewer app called FoxitReader. I can define it as the default pdf viewer app in the settings , but I cannot set it by editing the Registry.

I tried with: HKEY_CURRENT_USER/Software/Microsoft/Windows/CurrentVersion/Explorer/FileExt/.pdf

I also tried HKEY_CURRENT_USER\Software\Classes\MIME\Database\Content Type\application/pdf and set the CLSID to the CLSID of FoxitReader.Document,

Or Computer\HKEY_LOCAL_MACHINE\SOFTWARE\Classes.pdf\PersistentHandler with the CLSID

or HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts.pdf

Those do add this app into the Open list, but none of them can set FoxitReader as the default PDF viewer.
When I double click the pdf file, it still ask me to choose an app to open it instead of opening it directly in FoxitReader.

How could I set it as my default PDF viewer app in the Registry?

Answer 1

The default application is in HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.pdf\UserChoice . As you state, OpenWithList gives all the choices registered for this filetype. In the example below, it points to PDFXCview.exe, rather than Foxit.

Note that Applications\PDFXCview.exe uses indirection, not the absolute path to the executable. Applications\PDFXCview.exe, in turn, is defined in HKEY_CLASSES_ROOT\Applications\PDFXCview.exe and referenced in \HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\ApplicationAssociationToasts. A similar association should be set for each installed application, including Foxit.

You might look at Nirsoft's FileTypesMan to explore the file type associations, which can help point you to the correct Registry keys.

Answer 2

I know this an old question, but thought I would contribute an answer anyways. You can change the default program under the HKCR (HKEY_CLASSES_ROOT) registry hive.

Under HKCR, locate the registry key for the file extension you are intersted in (.pdf). Under that key should be a string value named "(Default)". Open that value to specify the program ID of the program you want to be the default app for that file type.

For example: to specify the default for .pdf as Foxit Phantom, you want to use Foxit's program ID which is "FoxitReader.Document". To change to Adobe Acrobat, it's "AcroExch.Document.DC".

Quick tip - each filety key will contain a subkey named "OpenWithProgids". The registry values listed under that subkey will represent all the prog IDs registered to open that extension. (i.e. under .pdf you should see FoxitReader.Document, AcroExch.Document.DC, and any other PDF reader/editor software you have installed.) This isn't necessarily a comprehensive list of all programs you could use - but it's a good start and should contain the programs that are safe to use.

Answer 3

In the accepted answer, it is implied that one should change the data for the registry value ProgId in key HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.pdf\UserChoice. This would not work, since in Windows 10 the default application is protected by a Hash value, which changes upon each change in UserChoice.

One way of circumventing this is by using the SetUserFTA utility, as described here. The command line would be

> SetUserFTA.exe .pdf Applications\PDFXCview.exe

Answer 4

Not an answer to the question, but I found that Edge takes over the PDF extension many times.

To avoid this (and to work like Windows 7) do the following:

• Deleted all keys except UserChoice in HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Explorer\FileExts\.pdf.
• Delete all values inside key UserChoice.
• Set the permissions of the key UserChoice to deny to Everyone.

Voila. Edge will never take over your PDFs anymore.