How to Restore Default Apps for File Type Associations in Windows 10


A default app is the program that Windows uses automatically when you open a particular file type or protocol.

Default app associations for file extensions are a per user setting by default, so you will need to be signed in to the user account you want to restore the default associations of a file extension for.

This tutorial will show you how to restore the default registry entries and app associations of a file extension type or protocol of your choice in Windows 10.

This can be helpful for example when a file extension type opens with the wrong app by default.

Contents

• Option One: To Reset All File Associations to Microsoft Recommended Defaults
• Option Two: To Restore Specific File Type or Protocol Association to Default

OPTION ONE

To Reset All File Associations to Microsoft Recommended Defaults

This option will reset all file type and protocol associations to the Microsoft recommended defaults for only your user account.

1 For how, see: How to Choose Default Apps to Open Files with in Windows 10

OPTION TWO

To Restore Specific File Type or Protocol Association to Default

This option will reset the associations, icon, and registry entries of the downloaded file type or protocol back to default.

The list of default file extension and protocol associations available to download in the table below is just a start for now, and is a work in progress. I will constantly be adding more to the list, but if you need one that is not yet listed, then please post a request for it. I'll be happy to get it added to the list.

If you're running Windows 10 22H2 with the latest updates, you'll need to follow this tutorial first:

Enable or Disable UserChoice Protection Driver (UCPD) in Windows 11 and 10 | Windows 11 Forum

1 Click/tap on the link of the file type or protocol in the table below that you would like to restore the default associations of to download its .reg file.

2 Save the .reg file to your desktop.

3 Double click/tap on the downloaded .reg file to merge it.

4 When prompted, click/tap on Run, Yes (UAC), Yes, and OK to approve the merge.

If you are signed in as a standard user account, then you will also get a Cannot import type error. Just click/tap OK for it. The part of the downloaded .reg file that is responsible for all users can only be successfully merged by an administrator account. The downloaded .reg file will still restore the default associations for your account.

If the .reg file is not able to Merge, then double check in Default Apps to make sure that the .reg file extension has its Current Default program set as Registry Editor (C:\Windows\regedit.exe). Afterwards, try merging the .reg file again.

5 Sign out and sign in, or restart the computer to apply.

6 If you are logged in as a standard user and this still does not help, then have the administrator also merge the needed .reg file for the listed file extension or protocol below while logged into their administrator account.

7 When finished, you can delete the downloaded .reg file if you like.

If you would like to download all available file extensions from the table below at once, here's a ZIP file of them.

Download

File Type or Protocol	Default App	Description
ani		Animated Cursor
AudioCD		Audio CD protocol associations
avi	Movies & TV	Audio Video Interleave (AVI) files
bak		Usually used to rename a file extension of a file with to make it a backup copy.
bat		Windows batch file
bin		BIN file
bmp	Photos	Bitmap image file
cab		Cabinet file
chm	Microsoft HTML Help Executable	Compiled HTML Help file
cmd		Windows Command Script
com		MS-DOS Application
crl	Crypto Shell Extensions	Certificate Revocation list
css	Notepad	Cascading Style Sheet document
cur		Cursor
dat		Generic data file created by a specific app; typically accessed only by the app that created the file; may contain data in text or binary format; text-based DAT files can be viewed in a text editor.
dds		DirectDraw Surface (DDS_ file
diagcab	Diagnostics Troubleshooting Wizard	Troubleshooting Pack Cabinet file
Directory		Directory protocol associations
divx	Movies & TV	DivX video file
dll		Application extension
Drive		Drives
epub	Microsoft Edge	Electronic publication file (aka: eBook)
exe		Executable application files
flac	Grove Music	A FLAC file is an audio file compressed in the Free Lossless Audio Codec (FLAC) format, which is an open source lossless audio compression format. It is similar to an .MP3 file, but is compressed without any loss in quality or loss of any original audio data.
Folder		All folders except library
gif	Photos	Graphics Interchange Format (GIF) image files
hlp	Windows Winhlp32 Stub	Help file
htm	Microsoft Edge	HTML (Hypertext Mark-up Language) document files
html	Microsoft Edge	HTML (Hypertext Mark-up Language) document files
http	Microsoft Edge	URL: HyperText Transfer Protocol
ico	Photos	Icon file
ics	Calendar	Calendar file
img		CD or DVD image file
inf	Notepad	Setup information file
ini	Notepad	Configuration settings
iso		Disk image file
jpe	Photos	Joint Photographic Experts Group (JPEG) image file
jpeg	Photos	Joint Photographic Experts Group (JPEG) image file
jpg	Photos	Joint Photographic Experts Group (JPEG) image file
js	Microsoft Windows Based Script Host	JavaScript file
json		A JSON file is a file that stores simple data structures and objects in JavaScript Object Notation (JSON) format, which is a standard data interchange format. It is primarily used for transmitting data between a web application and a server. JSON files are lightweight, text-based, human-readable, and can be edited using a text editor.
lib		Library file
library-ms		Libraries
lnk		Shortcut
log	Notepad	Text document file that Windows writes a record of events to.
lst		Text file that contains data.
mailto		URL:MailTo Protocol
mov	Movies & TV	Movie file
mp3	Groove Music	MP3 sound format file
mp4	Movies & TV	MPEG-4 movie file
mpeg	Windows Media Player	Movie clip
mpg	Windows Media Player	Movie clip
msc	Microsoft Management Console	Microsoft Common Console Document
msi	Windows Installer	Windows Installer Package
msp	Windows Installer	Windows Installer Patch
msu	Windows Update Standalone Installer	Windows Update Standalone Package
mui		Multilingual User Interface files are resource files that are used by Windows. The MUI files contain resources that allow you to change your Windows interface to display different languages.
Open with - > Choose default program		This is for what opens when you right click on a file, click on Open with, and click on Choose default program
Package		Resource package file.
pdf	Microsoft Edge	Portable Document Format (PDF) file.
png	Photos	Portable Network Graphics (PNG) is a bitmap compression method for image files. PNG supports 16.7 million colors, it is lossless and also supports index color, grayscale, true color, transparency, and is streamable. It is thus the best compression method (better than GIF or JPEG) for use on the web.
ps1	Notepad	Windows PowerShell Script
RDP	Remote Desktop Connection (mstsc.exe)	Remote Desktop Connection
reg	Registry Editor	Registration entries
res		Resource file
rtf	WordPad	Rich Text Document file
scr		Screen saver
sys		System file
svg	Internet Explorer	Scalable Vector Graphics document
theme	Personalization CPL	Windows theme file
themepack	Personalization CPL	Windows theme pack file
tif	Windows Photo Viewer	Tagged Image files Format.
tiff	Windows Photo Viewer	Tagged Image files Format.
txt	Notepad	Text document file
url	Internet Browser	Internet shortcut
vbs	Microsoft Windows Based Script Host (wscript.exe)	VBScript Script File
vhd		Virtual Hard Disk image file
vhdx		Hyper-V Virtual Hard Disk image file
wav	Groove Music	Wave audio file
webm	Movies & TV	A WEBM file is a compressed video saved in the WebM format, an open, high-quality video standard.
wma	Groove Music	Windows Media Audio file
wmv	Movies & TV	Windows Media Audio/Video file
xml	Internet Explorer	XML Document
xps	XPS Viewer	XPS Document
zip		Compressed (zipped) folder

That's it,
Shawn Brink

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