excel 2010 open in separate windows

We are trying to open excel in separate windows for a user in excel 2010.  I did the registry edit trick for xls and xlsx files and .xls files will open in new windows, which is great.  However, when he tries to open .xlsx files, it is not working.  It opens a blank excel form.  Any ideas?
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TomBallaAuthor Commented:
I have done that already.  The only thing that looks different is
"C:\Program Files\Microsoft Office\Office14\EXCEL.EXE" /e "%1"
on his computer it says
"C:\Program Files\Microsoft Office\Office14\EXCEL.EXE" /dde "%1"

It has /dde instead of just /e.  Anybody know what that stands for?
Harper McDonaldCommented:
1. Open one instance of Excel 2010
2. Click on the Office Button (top left hand corner)
3. Click Excel Options
4. Go to the Advanced section on the left
5. Scroll down to the "Display" heading
6. Tick "Show all windows in the Taskbar"

Worked for me...

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Microsoft Excel

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