Windows 7 – How do I force Excel (and other Microsoft Office products) to stop opening files in the same application?

Whenever I “double click” on an Excel file and another Excel file is open, the newly opened file automatically opens in the same application window as the previously opened Excel file. This isn’t limited to just Excel, as I’ve seen Word do this as well. This poses a problem when wanting to compare documents side by side.  

The current solution I have for this is to actually open another Excel or Word instance, and then open the file from within that application window itself. Is there a way to force Office to open a new instance of the application when double clicking on the file icons?

I’m currently using Office 2007 and Windows XP, but I’ve seen this on Office 2010 and Windows Vista and 7. I’m looking for an overall solution if possible.

Solution:

I have Office 2010 and the only app that does this for me is Excel.

A posting on PC Review, How to open vista excel in multiple windows versus 1 window? explains how to set this up:

  1. Use the File Association Settings
  2. You have to tell Excel not to use DDE to open the worksheet.
  3. Open Windows Explorer, Tools, Options, File Types
  4. Scroll down to XLS
  5. Select Advance Button
  6. Click on OPEN in the Actions window, Then Edit
  7. On the 2nd line for application used add "%1".
  8. Make sure to put the quotes around %1.
  9. Example …Excel.exe" /e "%1"
  10. Write down what you see in the DDE Section.
  11. You will need this information if you want to return to the original settings.
  12. Now DeSelect Use DDE

When you double click on any XLS file a separate instance of excel will run.

Another advantage is that you can open more than one XLS file with the samename