Back in the good old days with Windows XP, things were a little easier with performing simple tasks. One that comes to mind is file types. With XP you can easily associate and unassociate file types to a program or application, from the Control Panel or by selecting: Tools \ Folder Options on the menu of a folder.
With Vista, for some unknown reason, you can only associate file types, but you can not unassociate (delete) a file type completely. The only option allowed is to associate the file to another program or application. Until now…
First, let's look at two ways to find where File Type Associations lives in Vista. The easiest way is from the Start Menu, by clicking on Start \ Default Programs.
Then click on Associate a file type or protocol with a program.
The second way is from the Control Panel by clicking on Start \ Control Panel \ Programs then clicking on Make a file type always open in a specific program (under Default Programs).
Once you have accessed the window for file type association, you can easily associate (add) or change (modify) an existing file type, by highlighting a file type, then clicking on the Change Program… button.
NOTE: You will need to click the small down arrow to see the list of Other Programs.
To remove (delete) a file type association, you can use a great utility found on winhelponline.com to unassociate file types.
Just download, unzipp and click on Unassoc.exe. No install is required.
To use, just find the file type you want to delete and click on the Remove file association button. The file type association will be deleted from the registry. Vista will then treat it as an unknown file type.
Now, the only functionality missing with File types in Vista, compared to XP, is the capability to change icons and create a new file type. If you come across how to do this, let us know!