Default Programs

See every file type and protocol on your PC and which program opens it — and fix the ones that got hijacked.

What it does

File associations are the mapping between a file type (like .pdf or .mp3) or a protocol (like http:// or mailto:) and the program that opens it. Windows installations tend to drift over time — a new app sets itself as default, an update undoes your choice, Microsoft tries to herd you back to Edge. The built-in Windows Settings page only lets you change things one at a time and is often missing obscure types.

TuneBit lists every association in a single grid so you can see what's going on and fix anything that's wrong.

The grid

Three columns:

Extension / Protocol — the file type (.jpg) or protocol (http).
Current App — which program is set to open it right now.
Status — colored badge. Saved means this matches your last saved snapshot. Changed means something has reassigned it since. New means it didn't exist in your snapshot.

Actions

Save Current Defaults

Takes a snapshot of every current association. This becomes your "known good" baseline for future comparisons. Run this after you've finished setting up a fresh PC exactly the way you like it.

Restore Saved Defaults

Reverts every association back to whatever it was in your last snapshot. Great after a Windows Feature Update (which often silently resets defaults) or after installing a pushy app that claimed more file types than it should have.

View Changes Only

Filters the grid to show just the associations that differ from your snapshot. Much easier than scrolling through hundreds of unchanged rows.

Quick Set presets

One-click shortcuts to change a whole bundle of related associations at once:

Chrome for Web — sets Chrome as the default for HTTP, HTTPS, HTML, and related web types.
VLC for Media — sets VLC for every common audio and video extension (.mp3, .mp4, .mkv, .flac, etc.).
Custom — lets you pick a program and tick which file types should use it.

Presets use Windows' own association API, so changes take effect immediately and survive reboots.

How to use it

Go to Other → Default Programs. The page populates automatically.
Click Save Current Defaults once, after you've set up your system the way you like it.
Later on, if something starts opening in the wrong app, come back and click View Changes Only. You'll see what got hijacked.
Click Restore Saved Defaults to revert, or use a Quick Set preset to switch everything at once.

The Windows 11 gotcha: Windows 11 doesn't let you change the default browser with a single setting anymore — you have to set each of HTTP, HTTPS, HTM, HTML, PDF, and a few others one-by-one. TuneBit's Chrome for Web (or equivalent) preset does all of them in one shot.

Restore Saved Defaults only works if you've saved a snapshot. If you click it and nothing happens, it's because no baseline exists yet. Click Save Current Defaults first next time you have your system configured properly.