I just installed Win2000 and Office 97 on a brand new
computer.  Clean install, essentially nothing else on the
computer yet.  I have a few Excel files, some that were
created previously and a couple that were created on this
machine with this copy of Excel.

If I double click on an Excel file in Explorer, Excel
launches, opens the file, and then tries to open the file
a second time!  Anytime I try to open something in this
way I get an error that says something like "A document
with the name "xyz.xls" is already open.  You cannot open
two documents with the same name..."

If I start Excel and open the file from the File|Open menu
it works normally.

I do not have my settings such that I only need a single
mouse click; everything else works normally (a double
click on a TXT file opens one copy of it in Notepad, a
double click on a JPEG opens it in PSP, ...)

What is going on????

In Explorer|Folder Options|File Types the XLS extension
opens with
C:\...\excel.exe %1
and the Use DDE command is checked, with
[open("%1")]
What does all this mean?

TIA