Open Add Rule
Launch OpenWithGuard and select Add Rule in the sidebar.
Choose a file extension
Select a common extension such as .pdf, .docx, .png, or .zip. If the type is not listed, enter a custom extension in the file type field.
.pdf.docx.png.zipcustom extension
Choose an application
Select one of the applications registered for that file type. If the program is not shown, use Choose another app and select its executable file.
Choose the real application
Use the application you want Windows to launch for this extension. Do not select an installer or an unrelated helper executable.
Save the rule
Review the selected extension and application, then save. Open a file with that extension to confirm Windows launches the chosen application.
Pause, edit, or remove the rule
Return to Rules whenever you want to change the application, temporarily pause protection, or delete a rule you no longer need.