"No program is registered to open this file" in Word

When I click on a hyperlink in any Word 2003 document, the above warning
has begun to appear - the link does actually open, though, in IE6.

I recently tried out Firefox but couldn't get on with it and uninstalled
it. Might this have created the problem and would anyone have any thoughts
on how to correct it? I looked through the group but couldn't find
anything specifically relating to the problem happening when clicking on
hyperlinks in Word documents.

TIA,

Ian

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