If Windows doesn't recognize the file's extension, then the user is prompted with an ' Open with' dialog on ' How do you want to open this file?'.

Locate the file whose association you want to change or set.Whenever you try to open a file in Windows, the system checks the type of the file by reading its extension (known as ' Filename extension') and then launches the appropriate program associated with this type of file in order to open/view the file.

To change the program associated with a specific file, follow the steps below.

Type the associated extension and the description and actions of the file.Īssociate one file with a specific program.

Click View in the file menu and Folder Options.

Locate the file extension you want to remove and highlight it.

Otherwise, click New and create a new action.

If you want to modify a previous action, highlight it in the Actions list and edit it.

Click the Tools in the file menu and then click Folder Options.

If the program you want to select is not listed, click the Browse button, find the program's executable (.exe) file on the computer, and click OK to select that program.

Select the program you want to associate, open the file extension, and click OK.Locate the file extension you want to modify and highlight it.In Control Panel, type Default Programs in the search field in the upper-right corner and click the Default Programs selector.In the Choose an app pop-up window, select the program you want to associate with that file type.

Under the Default app column, click the name of the currently-selected default program.Under the Name column, locate the file extension you want to modify.On the right side, in the Default apps section, scroll down and click the Choose default apps by file type option.Press the Windows key, type Default apps, and press the Enter key.In the How do you want to open pop-up window, select the program you want to associate with that file type.Click the current default program or Choose a default option below the file type.In the Default apps window, scroll to the bottom and select Choose defaults by file type.Click the Associate a file type or protocol with a program option.In the Control Panel, click the Default Programs option.

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