Here's the deal...

Got a laptop running Office 2003.
Got a desktop running Office 2007.

I make changes to a workbook using my laptop. The file actually resides on
a network share.

I open the file on the desktop (in Excel 2007) even using the Windows
Explorer and double-clicking on the file on the network share, I don't see
the changes I made using the laptop.

If I use Windows Explorer on the desktop machine and tell the file to
synchronize, then I can see the changes.

I do not want to explore out to the network share and synchronize before
opening any and all documents. How do I tell Excel to synchronize it before
opening it?