All of the developers at LavaBlast use three monitors; utilizing multiple monitors has significantly increased our efficiency. However, Microsoft Excel doesn’t work particularly well in a multi-monitor setup. By default, every time you open a new Excel file, its contents are displayed within the same instance. You have to manually launch other instances of Excel to have one instance per monitor, which is time consuming.

It is possible to configure Microsoft Excel to load one Window per file, but it involves a number of obscure configuration settings & registry changes. Every time we move to a new machine, this configuration needs to be redone. The information is spread out on a number of sites/forums and it takes a while to re-discover the sources. his post aims at centralizing this information.

In particular, this post focuses on Microsoft Excel 2010 on Windows 7 64-bit. I believe the fix works on other versions as well; feel free to comment on this blog post if the steps are different.

Step 1) Force Excel To Open Multiple Windows

Excel 2010:

  • File –> Options –> Advanced –> Scroll down into the “General” section –> Check the “Ignore other applications that use Dynamic Data Exchange (DDE)” checkbox image

Excel 2007:

  • Office Icon in the top left corner of Excel –> Excel Options –> Advanced  -> Scroll down into the “General” section –> Check the “Ignore other applications that use Dynamic Data Exchange (DDE)” checkbox

Once this change is done, every time you double click on an Excel file in Windows Explorer, a new instance of Excel will open. However, you’ll probably encounter the following error.

Step 2) Fixing “There was a problem sending the command to the program”

Each Excel file you open from Windows Explorer now launches in its own separate window. However, Excel spits out “There was a problem sending the command to the program” and leaves the Excel window blank.  You can drag & drop your existing file to this window to open it, but this is still painful. We will need to change the system registry to solve this issue; please refrain from doing this is you are not comfortable with the reg edit tool.

  1. Launch regedit
  2. Rename the HKEY_CLASSES_ROOT\Excel.Sheet.8\shell\Open\ddeexec  key to HKEY_CLASSES_ROOT\Excel.Sheet.8\shell\Open\ddeexec.bak
  3. Edit HKEY_CLASSES_ROOT\Excel.Sheet.8\shell\Open\command\(Default).  Change /dde to “%1” in the value.
  4. As an example, mine was from "C:\Program Files (x86)\Microsoft Office\Office14\EXCEL.EXE" /dde to "C:\Program Files (x86)\Microsoft Office\Office14\EXCEL.EXE" "%1"
  5. Edit HKEY_CLASSES_ROOT\Excel.Sheet.8\shell\Open\command\command. Change /dde to “%1” in the value.
  6. As an example, mine was from ykG^V5!!!!!!!!!MKKSkEXCELFiles>VijqBof(Y8'w!FId1gLQ /dde to ykG^V5!!!!!!!!!MKKSkEXCELFiles>VijqBof(Y8'w!FId1gLQ "%1"
  7. Rename the HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\Open\ddeexec key to HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\Open\ddeexec.bak
  8. Edit HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\Open\command\(Default). Change /dde to “%1” in the value.
  9. Edit HKEY_CLASSES_ROOT\Excel.Sheet.12\shell\Open\command\command. Change /dde to “%1” in the value.


Excel should now load separate Windows for each file you open. This setup will consume more memory, but will vastly increase your productivity.

Troubleshooting note:

  • Ensure you used “%1” with the surrounding quotes (not this: %1) in the above registry changes. Otherwise, you will get an error message: “’{file}’ could not be found. Check the spelling of the file name, and verify that the file location is correct.”

Thanks to Turbo2001rt  for the final important tweaks.