Microsoft recommends the C:\Program Files folder for the default installation destination. It’s a convention that ensures proper inter-operation between your program and the OS’s application and security models. So, once software programs are installed, they go by default to C:\Program files on the computer. This can, however, be changed by selecting another folder or location or partition.  To change the default installation folder, the data must be modified in the ProgramFilesDir key and a new path must be chosen for the installation folder. Windows uses the System Disk for installing any new applications; that is, if your Windows is installed on the C Drive, the default folder where all the applications you install would automatically show up as C:\Program Files, unless, of course, you change it manually while installing the application’s locations. WARNING: Do note that Microsoft does not support changing the location of the Program Files folder by modifying the ProgramFilesDir registry value. It states that if you change the location of the Program Files folder, you may experience problems with some Microsoft programs or with some software updates. And so as such, we do not recommend you try it – as it has worked for some, and not for others – esp. on recent Windows 11/10 builds. If at all you decide to try this suggestion, we recommend that you back up your registry and create a system restore point first. TIP: Windows 11/10 makes things easy. You can easily move Windows Apps to another Drive and change their Install location.

Hoa to change default Program Files installation directory location in Windows 11/10

If you almost always prefer not to install on the System Disk, but instead on another partition, say, the D drive, then rather than changing the default location every time, you can edit the registry as follows: Before you begin, create a system restore point first. Now open Regedit and navigate to the following key:

Now in the right pane, look for the value ProgramFilesDir and/or ProgramFilesDir (x86) depending on whether your Windows is 32-bit or 64-bit. Double-click on it and in the box which opens up, change its Value data from C:\Program Files to say, D:\Program Files. Click OK. Exit. The default directory for installing all your programs shall now be D:\Program Files. If you are using Windows 64-bit, you must change the value of ProgramFilesDir and ProgramFilesDir (x86).

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How to change the default location of the Documents folder or profile personal filesHow to change the default install location of Windows Store Apps.