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Change File associations

To set File Associations in Windows 7 or Vista,

Open Control Panel > Control Panel Home > Default Programs > Set Associations. Select a file type in the list and click Change Program.

You can also

Right click the file whose association you want to change > Properties > General tab > Type Of File > Change > Choose a program from the list or recommended or other programs or else click Browse to select one.

All here @ http://www.winvistaclub.com/t19.html