Lost File Association
It sounds to me as if the file association for opening the Word file has been lost. File associations are used by Windows to determine which program should be launched for working with particular file types. Occasionally, these associations are changed or removed, either on purpose or inadvertently, thus confusing the operating system. In this case, when clicking on a Word .doc file, your computer doesn’t understand that this file type requires Word to be launched.
Resetting the Word File Association
Fortunately, it’s easy to change the file association. Assuming it’s a .doc file that you are trying to create an association for, right-click the Start button and choose Explore. This opens Windows Explorer. Navigate to a .doc document (it doesn’t need to be the one you have on your desktop). Right-click the .doc document and choose Open or Open With, depending on the choice presented. Windows will display a listing of suitable programs, but Word may not be listed. If Word is listed, click it. If not, click Browse and then browse until you can select Word. Once Word is selected, make sure to place a mark in the box that sets this program as the default program type for the selected file type. That will set the file association.
Changing the Program Associated with a Desktop Document
You can also change the program used to open documents that you have stored on your Desktop. Right-click the Desktop icon and choose Properties. You should see the file name listed followed by “Type of file.” Look for “Opens with” and then click the Change button. Windows will list suggested programs. Choose the desired program and then click OK. You will also have an option to set the desired program to the default program for that file type.

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