1. In Windows Explorer, choose the Tools/Folder Options menu.
2. Click on the File Types tab
3. Scroll down and select the "XLS Microsoft Excel Worksheet" item
4. Click the "Advanced" button
5. Uncheck the "Browse in same window" option
6. Click on "Open" in the Actions list
7. Click the "Edit" button
8. Click in the "Application used to perform action:" box
9. Scroll to the very end. It will say something like ...EXCEL.EXE" /e %1
10. Put quotes around the %1, so it now ends with ...EXCEL.EXE" /e "%1"
11. Click OK twice, Close once, and you should be in business