A full overview of all Default File Associations.
This list is for reference after changing default programs, this list was complined right after installing Windows 8.1 Pro. You are free to share this list, but please put a link back to this post.
| File | Description | Default App / Application |
| .3g2 | 3G2 File | Video |
| .3gp | 3GP File | Video |
| .3gp2 | 3GPP2 Audio/Video | Windows Media Player |
| .3gpp | 3GPP File | Video |
| .aac | AAC File | Music |
| .adt | ADTS Audio | Windows Media Player |
| .adts | ADTS Audio | Windows Media Player |
| .aif | AIFF Format Sound | Windows Media Player |
| .aifc | AIFF Format Sound | Windows Media Player |
| .aiff | AIFF Format Sound | Windows Media Player |
| .appcontent-ms | Application Content | Windows Shell Common Dll |
| .application | Application Manifest | ClickOnce Application Deployment Support Library |
| .appref-ms | Application Reference | ClickOnce Application Deployment Support Library |
| .arw | ARW File | Photos |
| .asf | Windows Media Audio/Video file | Windows Media Player |
| .asx | Windows Media Audio/Video playlist | Windows Media Player |
| .au | AU Format Sound | Windows Media Player |
| .avi | AVI File | Video |
| .blg | Performance Monitor File | Resource and Performance Monitor |
| .bmp | BMP File | Photos |
| .camp | WCS Viewing Condition Profile | Microsoft Color Control Panel |
| .cat | Security Catalog | Crypto Shell Extensions |
| .cda | CD Audio Track | Windows Media Player |
| .cdmp | WCS Device Profile | Microsoft Color Control Panel |
| .cdxml | Windows PowerShell Cmdlet Definition XML Document | Notepad |
| .cer | Security Certificate | Crypto Shell Extensions |
| .chm | Compiled HTML Help file | Microsoft® HTML Help Executable |
| .compositefont | Composite Font File | Notepad |
| .contact | Contact file | Windows Contacts |
| .cpl | Control panel item | Windows Control Panel |
| .cr2 | CR2 File | Photos |
| .crl | Certificate Revocation List | Crypto Shell Extensions |
| .crt | Security Certificate | Crypto Shell Extensions |
| .crw | CRW File | Photos |
| .css | Cascading Style Sheet Document | Notepad |
| .dctx | Open Extended Dictionary | Microsoft IME Open Extended Dictionary Module |
| .dctxc | Open Extended Dictionary | Microsoft IME Open Extended Dictionary Module |
| .der | Security Certificate | Crypto Shell Extensions |
| .deskthemepack | Windows Desktop Theme Pack File | Personalization CPL |
| .diagcab | Troubleshooting Pack Cabinet | Diagnostics Troubleshooting Wizard |
| .diagcfg | Troubleshooting Pack Configuration | Diagnostics Troubleshooting Wizard |
| .diagpkg | Troubleshooting Pack | Diagnostics Troubleshooting Wizard |
| .dib | DIB File | Photos |
| .divx | DIVX File | Video |
| .docx | Office Open XML Document | WordPad |
| .dvr-ms | Microsoft Recorded TV Show | Windows Media Player |
| .dwfx | XPS Document | XPS Viewer |
| .easmx | XPS Document | XPS Viewer |
| .edrwx | XPS Document | XPS Viewer |
| .emf | EMF File | Paint |
| .eprtx | XPS Document | XPS Viewer |
| .erf | ERF File | Photos |
| .evt | Classic Event Log | Event Viewer Snapin Launcher |
| .evtx | Event Log | Event Viewer Snapin Launcher |
| .fon | Font file | Windows Font Viewer |
| .gif | GIF File | Photos |
| .gmmp | WCS Gamut Mapping Profile | Microsoft Color Control Panel |
| .group | Group file | Windows Contacts |
| .hlp | Help file | Windows Winhlp32 Stub |
| .hta | HTML Application | Microsoft (R) HTML Application host |
| .htm | HTML Document | Internet Explorer |
| .html | HTML Document | Internet Explorer |
| .icc | ICC Profile | Microsoft Color Control Panel |
| .icm | ICC Profile | Microsoft Color Control Panel |
| .ico | Icon | Windows Photo Viewer |
| .imesx | IME Search provider definition | IME search module |
| .inf | Setup Information | Notepad |
| .ini | Configuration settings | Notepad |
| .jfif | JFIF File | Photos |
| .jnt | Journal Document | Windows Journal |
| .jpe | JPE File | Photos |
| .jpeg | JPEG File | Photos |
| .jpg | JPG File | Photos |
| .js | JavaScript File | Microsoft ® Windows Based Script Host |
| .jse | JScript Encoded Script File | Microsoft ® Windows Based Script Host |
| .jtp | Journal Template | Windows Journal |
| .jtx | XPS Document | XPS Viewer |
| .jxr | JXR File | Photos |
| .kdc | KDC File | Photos |
| .log | Text Document | Notepad |
| .m1v | Movie Clip | Windows Media Player |
| .m2t | M2T File | Not selected |
| .m2ts | M2TS File | Not selected |
| .m2v | Movie Clip | Windows Media Player |
| .m3u | M3U File | Not selected |
| .m4a | M4A File | Music |
| .m4v | M4V File | Video |
| .mfp | Macromedia Flash Paper | Internet Explorer |
| .mht | MHTML Document | Internet Explorer |
| .mhtml | MHTML Document | Internet Explorer |
| .mid | MIDI Sequence | Windows Media Player |
| .midi | MIDI Sequence | Windows Media Player |
| .mig | Easy Transfer file | Windows Easy Transfer Application |
| .mlc | Language Pack File | Language Pack Installer |
| .mod | MOD File | Not selected |
| .mov | MOV File | Video |
| .mp2 | MP3 Format Sound | Windows Media Player |
| .mp2v | Movie Clip | Windows Media Player |
| .mp3 | MP3 File | Music |
| .mp4 | MP4 File | Video |
| .mp4v | MP4V File | Video |
| .mpa | Movie Clip | Windows Media Player |
| .mpe | Movie Clip | Windows Media Player |
| .mpeg | Movie Clip | Windows Media Player |
| .mpg | Movie Clip | Windows Media Player |
| .mpv2 | MPV2 File | Not selected |
| .mrw | MRW File | Photos |
| .msc | Microsoft Common Console Document | Microsoft Management Console |
| .msi | Windows Installer Package | Windows® installer |
| .msp | Windows Installer Patch | Windows® installer |
| .msrcincident | Windows Remote Assistance Invitation | Windows Remote Assistance |
| .msu | Microsoft Update Standalone Package | Windows Update Standalone Installer |
| .mts | AVCHD Video | Windows Media Player |
| .nef | NEF File | Photos |
| .nfo | System Information File | System Information |
| .nrw | NRW File | Photos |
| .odt | OpenDocument Text | WordPad |
| .orf | ORF File | Photos |
| .otf | OpenType font file | Windows Font Viewer |
| .oxps | OXPS File | Reader |
| .p12 | Personal Information Exchange | Crypto Shell Extensions |
| .p7b | PKCS #7 Certificates | Crypto Shell Extensions |
| .p7c | Certificate file | Windows Contacts |
| .p7r | Certificate Request Response | Crypto Shell Extensions |
| .p7s | PKCS #7 Signature | Crypto Shell Extensions |
| .pano | PANO File | Photos |
| .partial | Partial Download | Internet Explorer |
| .pbk | Dial-Up Phonebook | Remote Access Phonebook |
| PDF File | Reader | |
| .pef | PEF File | Photos |
| .perfmoncfg | Performance Monitor Configuration | Resource and Performance Monitor |
| .pfm | Type 1 Font file | Windows Font Viewer |
| .pfx | Personal Information Exchange | Crypto Shell Extensions |
| .png | PNG File | Photos |
| .prf | PICS Rules File | Internet Ratings and Local User Management DLL |
| .printerexport | Printer Migration File | PrintBrm Application |
| .ps1 | Windows PowerShell Script | Notepad |
| .ps1xml | Windows PowerShell XML Document | Notepad |
| .psc1 | Windows PowerShell Console File | Windows PowerShell |
| .psd1 | Windows PowerShell Data File | Notepad |
| .psm1 | Windows PowerShell Script Module | Notepad |
| .pssc | Windows PowerShell Session Configuration File | Notepad |
| .qds | Directory Query | Directory Service Find |
| .raf | RAF File | Photos |
| .rat | Rating System File | Internet Ratings and Local User Management DLL |
| .raw | RAW File | Photos |
| .rdp | Remote Desktop Connection | Remote Desktop Connection |
| .reg | Registration Entries | Registry Editor |
| .resmoncfg | Resource Monitor Configuration | Resource and Performance Monitor |
| .rle | RLE File | Paint |
| .rmi | MIDI Sequence | Windows Media Player |
| .rtf | Rich Text Document | WordPad |
| .rw2 | RW2 File | Photos |
| .rwl | RWL File | Photos |
| .scp | Text Document | Notepad |
| .sct | Windows Script Component | Notepad |
| .settingcontent-ms | Setting Content | Windows Shell Common Dll |
| .snd | AU Format Sound | Windows Media Player |
| .spc | PKCS #7 Certificates | Crypto Shell Extensions |
| .sr2 | SR2 File | Photos |
| .srw | SRW File | Photos |
| .sst | Microsoft Serialized Certificate Store | Crypto Shell Extensions |
| .svg | SVG Document | Internet Explorer |
| .theme | Windows Theme File | Personalization CPL |
| .themepack | Windows Theme Pack File | Personalization CPL |
| .tif | TIF File | Reader |
| .tiff | TIFF File | Reader |
| .tod | TOD File | Video |
| .ts | MPEG-2 TS Video | Windows Media Player |
| .ttc | TrueType collection font file | Windows Font Viewer |
| .ttf | TrueType font file | Windows Font Viewer |
| .tts | MPEG-2 TS Video | Windows Media Player |
| .txt | Text Document | Notepad |
| .udl | Microsoft Data Link | OLE DB Core Services |
| .url | Internet Shortcut | Internet Browser |
| .vbe | VBScript Encoded Script File | Microsoft ® Windows Based Script Host |
| .vbs | VBScript Script File | Microsoft ® Windows Based Script Host |
| .vcf | VCard file | Windows Contacts |
| .wab | WAB file | Windows Contacts |
| .wav | WAV File | Music |
| .wax | Windows Media Audio shortcut | Windows Media Player |
| .wcx | RemoteApp and Desktop Connections Configuration File | Extensible Wizards Host Process |
| .wdp | WDP File | Photos |
| .webpnp | Web Point And Print File | Support exe for Internet Printing |
| .website | Pinned Site Shortcut | Internet Explorer |
| .wm | WM File | Video |
| .wma | WMA File | Music |
| .wmd | Windows Media Player Download Package | Windows Media Player |
| .wmf | WMF File | Paint |
| .wms | Windows Media Player Skin File | Windows Media Player |
| .wmv | WMV File | Video |
| .wmx | Windows Media Audio/Video playlist | Windows Media Player |
| .wmz | Windows Media Player Skin Package | Windows Media Player |
| .workfolders | Microsoft Workfolders | Windows Control Panel |
| .wpl | Windows Media playlist | Windows Media Player |
| .wsc | Windows Script Component | Notepad |
| .wsf | Windows Script File | Microsoft ® Windows Based Script Host |
| .wsh | Windows Script Host Settings File | Microsoft ® Windows Based Script Host |
| .wtv | Windows Recorded TV Show | Windows Media Player |
| .wtx | Text Document | Notepad |
| .wvx | Windows Media Audio/Video playlist | Windows Media Player |
| .xaml | Windows Markup File | Windows Presentation Foundation Host |
| .xbap | XAML Browser Application | Windows Presentation Foundation Host |
| .xht | XHTML Document | Internet Explorer |
| .xhtml | XHTML Document | Internet Explorer |
| .xml | XML Document | Internet Explorer |
| .xps | XPS File | Reader |
| .xrm-ms | XrML Digital License | Internet Explorer |
| .xsl | XSL Stylesheet | Internet Explorer |
| .xvid | XVID File | Video |
| .zpl | ZPL File | Music |
| AUDIOCALL-MESSENGER | URL:audiocall-messenger | Skype |
| AUDIOCALL-SKYPE-COM | URL:audiocall-skype-com | Skype |
| BINGFINANCE | URL:bingfinance | Finance |
| BINGFOODANDDRINK | URL:bingfoodanddrink | Food & Drink |
| BINGHEALTHNFITNESS | URL:binghealthnfitness | Health & Fitness |
| BINGMAPS | URL:bingmaps | Maps |
| BINGNEWS | URL:bingnews | News |
| BINGSPORTS | URL:bingsports | Sports |
| BINGTRAVEL | URL:bingtravel | Travel |
| BINGWEATHER | URL:bingweather | Weather |
| DLNA-PLAYSINGLE | URL:DLNA-PLAYSINGLE Protocol | Windows Media Player |
| EXPLORER.BURNSELECTION | File Explorer ‘Burn to disc’ button | Windows Explorer |
| EXPLORER.ERASEDISC | File Explorer ‘Erase this disc’ button | Windows Explorer |
| EXPLORER.ZIPSELECTION | File Explorer ‘Zip’ button | Windows Explorer |
| FTP | URL:File Transfer Protocol | Internet Explorer |
| HTTP | URL:HyperText Transfer Protocol | Internet Explorer |
| HTTPS | URL:HyperText Transfer Protocol with Privacy | Internet Explorer |
| LDAP | URL:LDAP Protocol | Windows Contacts |
| MAILTO | URL:mailto | |
| MESSAGE-MESSENGER | URL:message-messenger | Skype |
| MESSAGE-SKYPE-COM | URL:message-skype-com | Skype |
| MICROSOFTMUSIC | URL:microsoftmusic | Music |
| MICROSOFTVIDEO | URL:microsoftvideo | Video |
| MK | URL:MK Protocol | Internet Explorer |
| MMS | URL:MMS Protocol | Windows Media Player |
| MS-MAIL | URL:ms-mail | |
| PROFILE-FACEBOOK-COM | URL:profile-facebook-com | People |
| PROFILE-GOOGLE-COM | URL:profile-google-com | People |
| PROFILE-LINKEDIN-COM | URL:profile-linkedin-com | People |
| PROFILE-LYNC-COM | URL:profile-lync-com | People |
| PROFILE-MESSENGER | URL:profile-messenger | People |
| PROFILE-OUTLOOK-COM | URL:profile-outlook-com | People |
| PROFILE-SKYPE-COM | URL:profile-skype-com | People |
| PROFILE-TWITTER-COM | URL:profile-twitter-com | People |
| PROFILE-WEIBO-COM | URL:profile-weibo-com | People |
| PROFILE-YAHOO-COM | URL:profile-yahoo-com | People |
| RES | URL:RES Protocol | Internet Explorer |
| SEARCH | Windows Search protocol | Windows Explorer |
| SKYPE | URL:skype | Skype |
| SMS | URL:sms | Skype |
| TEL | URL:tel | Skype |
| VIDEOCALL-MESSENGER | URL:videocall-messenger | Skype |
| VIDEOCALL-SKYPE-COM | URL:videocall-skype-com | Skype |
| WINDOWS.CONTACT.CALL+OUTLOOK.COM | Call | Skype |
| WINDOWS.CONTACT.CALL+SKYPE.COM | Call | Skype |
| WINDOWS.CONTACT.CALL+TELEPHONE | Call | Skype |
| WINDOWS.CONTACT.MAP | Map | Maps |
| WINDOWS.CONTACT.MESSAGE+OUTLOOK.COM | Message | Skype |
| WINDOWS.CONTACT.MESSAGE+SKYPE.COM | Message | Skype |
| WINDOWS.CONTACT.MESSAGE+TELEPHONE | Message | Skype |
| WINDOWS.CONTACT.POST+FACEBOOK.COM | Post | People |
| WINDOWS.CONTACT.POST+TWITTER.COM | Post | People |
| WINDOWS.CONTACT.VIDEOCALL+OUTLOOK.COM | Video call | Skype |
| WINDOWS.CONTACT.VIDEOCALL+SKYPE.COM | Video call | Skype |
| WINDOWSREADINGLIST | URL:windowsreadinglist | Reading List |
| WLCALENDAR | URL:wlcalendar | Calendar |
| WLPEOPLE | URL:wlpeople | People |
| XBOXGAMES | URL:xboxgames | Games |
| List complined by Yuri Pustjens. |
