Using Vista Business Edition, Office 2007 Enterprise.

If I double-click on a spreadsheet saved with an earlier version of Excel,
all I get is a unusable blank window with a zoom bar at the top and no
toolbar or menu tabs, no control box, no anything. The only way I can close
the application at that point is by using Task Manager to end it.

However if I open Excel first then use the open menu or drag the file onto
Excel, it works OK.

Any ideas anyone?

TIA
Andrew