When opening a link ( website/email link ) from outlook in Windows Vista, the error stated in the title comes up. If the default browser is internet explorer, it is not enough and the default browser has to be specified at another place. The following has to be done to solve the issue.
1. Click Start-> Program Defaults
2. Set Program Access and Computer defaults.
3. Drop down the Custom option.
4. In choose a default browser click on: “Internet Explorer”.
Now the link should open in Internet Explorer.