I'm running Windows 7 64-bit (upgraded from Vista), as well as Office 2003. I notice that the Taskbar Thumbnail Preview feature doesn't work when I have two or more Excel files open. The preview boxes simply show the Excel icon instead of the file contents. I've done a bit of searching, and the best answer I've found is that Excel doesn't open files in separate "instances" (as Word does), but rather it opens multiple files in the same instance of the Excel program. I've found a few cumbersome workarounds to force-open separate instances of Excel, but none of the fixes are convenient. Does anyone know if there is a direct solution to this problem? I tried searching the Microsoft forums - no luck. Apologies if this question belongs in an Excel NG. If so, I'll re-post there. Thanks!