How to open an unknown file in Windows 10

Step-by-step instructions

Method 1: Choose a program already installed on your computer

  1. Double-click the unknown file and select the program you want to open the file from the dialog box.
  2. Check the checkbox if you want the selected program to always open the file type.
  3. Click "OK."

Method 2: Choose a program from the Microsoft Store

  1. Double-click the unknown file.
  2. Select "Look for an app in the Store" in the dialog box and click "OK."
  3. Click the icon of the program from the app results in the Microsoft Store that best fits your needs.
  4. Click "Get" or "Buy" on the program page to acquire, download, and install the app from the Microsoft Store.
  5. Once the program is downloaded and installed, double-click the unknown file to open it in the recently downloaded program.