In Windows 10, setting per-user file associations for a logged on user account has to be done only using Default Apps or the Open with dialog manually. If you try to change the user default registry entries using script or batch files, Windows 10 will reset the file association to Windows defaults, and you’ll see the annoying An App Default was Reset notification.
Microsoft says applications must not write to the
UserChoice registry key which stores the user-default association settings. This is because the user must be in control, not the programs. Programs competing with each other and arbitrarily changing the user-specific associations is not going to be good user experience. The
UserChoice key is a protected location, and the ProgID value is validated with a hash.
When you use Default Apps or Open with to set associations, Windows 10 generates the hash for each file type association. The hash generated is based on many inputs like user account SID, ProgId, registry time, etc., and perhaps other parameters.
Default Browser & File Association via Command-line in Windows 10
Users may sometimes need a shortcut method to set file associations for their user account without going through the Open with dialog or Default Apps every time. Some toggle switch or shortcut to change browser or file association defaults will be a great help for users.
Luckily, we have the SetuserFTA tool to do that. To set the file association and default browser via command-line, use the SetuserFTA utility written by Christoph Kolbicz. Kolbicz has reverse-engineered the hashing algorithm effectively. This utility generates the hash automatically and sets the defaults for you.
To change the default browser using command-line, use this syntax:
SetUserFTA.exe extension progid
It also supports URL protocols (e.g.,
To set Chrome as the default browser, run these commands:
SetuserFTA http ChromeHTML SetuserFTA https ChromeHTML SetuserFTA .htm ChromeHTML SetuserFTA .html ChromeHTML
SetuserFTA http FirefoxHTML SetuserFTA https FirefoxHTML SetuserFTA .htm FirefoxHTML SetuserFTA .html FirefoxHTML
SetuserFTA http OperaStable SetuserFTA htts OperaStable SetuserFTA .htm OperaStable SetuserFTA .html OperaStable
SetuserFTA http AppXq0fevzme2pys62n3e0fbqa7peapykr8v SetuserFTA https AppX90nv6nhay5n6a98fnetv7tpk64pp35es SetuserFTA microsoft-edge AppX7rm9drdg8sk7vqndwj3sdjw11x96jc0y SetuserFTA .htm AppX4hxtad77fbk3jkkeerkrm0ze94wjf3s9 SetuserFTA .html AppX4hxtad77fbk3jkkeerkrm0ze94wjf3s9
RELATED: See article How to Remove File Type Associations Using the Registry Editor for more information on File extension → ProgID mapping.
Default Image Viewer
To set Windows Photo Viewer as the default handler for .png and .jpg files, run:
SetuserFTA .jpg PhotoViewer.FileAssoc.Jpeg SetuserFTA .png PhotoViewer.FileAssoc.Png
Note that you’ll have applied the Windows Photo Viewer registry edit as in the article Restore Missing Windows Photo Viewer in Windows 10 for the above commands to work. Without the necessary ProgId registration, your files will show up as unknown file type.
To revert to Microsoft Photos as the default, use this command-line:
SetuserFTA .jpg AppX43hnxtbyyps62jhe9sqpdzxn1790zetc SetuserFTA .png AppX43hnxtbyyps62jhe9sqpdzxn1790zetc
ProgID vs “Applications\program.exe”
If an application doesn’t define a file class or Progid, you can mention the program’s exe as well, like
Applications\program.exe type as well. This works if the program is registered under
HKCR\Applications registry key.
For example, to set Notepad++ as the default editor for .txt files, run:
setuserfta .txt applications\notepad++.exe
To revert to default (
setuserfta .txt txtfile or setuserfta .txt applications\notepad.exe
You may create desktop shortcuts for the required commands to switch defaults quickly in a single click!
View current user defaults for all file types
To get the user defaults for all file types and URL protocols, run the command:
SetuserFTA makes the job of setting file associations easy.
Note: There is a similar utility from Danysys.com which I’ve not tested yet. If you want to check it out, visit Set File Type Association Default Application Command Line Windows 10 UserChoice Hash Internal Method
About the author
Ramesh Srinivasan founded Winhelponline.com back in 2005. He is passionate about Microsoft technologies and he has been a Microsoft Most Valuable Professional (MVP) for 10 consecutive years from 2003 to 2012.