The Open With dialog in Windows allows you to open a file using different programs. Also, you can create or change the file type association by selecting the “Always use the selected program to open this kind of file” checkbox in the Open With dialog.
Sometimes, users wrongly associate file types and end up having to reset the associations manually. To prevent users from changing file type associations using the Open with dialog, you can remove the “Always use the selected program to open this kind of file” checkbox.
1. Launch Regedit.exe and navigate to the following branch:
HKEY_CURRENT_USER\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
Note: If the above branch does not exist, you need to create it manually.
2. Create a new DWORD value named NoFileAssociate
3. Double-click NoFileAssociate and set its data to 1
4. Exit the Registry Editor.
The above registry change affects the current user account only. To implement the change for all users (system-wide), create the NoFileAssociate value in the following branch:
HKEY_LOCAL_MACHINE\Software\Microsoft\Windows\CurrentVersion\Policies\Explorer
The above edit when used in Windows 2000/XP, results in a grayed out “Always use the selected program…” checkbox. Whereas in Windows Vista and higher, the checkbox is removed completely.