Excel ERROR : There was a problem sending the command to the program

When you double-click an Excel workbook or a shortcut to an Excel workbook, Excel starts. However, the Excel workbook does not open, and you receive an error message.

The error message may be different, depending on the version of Windows that you are using.

In Windows 7 and Windows 8, you may see this error message:
There was a problem sending the command to the program.

In Windows Vista, you may see this error message:
Windows cannot find 'FilePath\FileName', Make sure you typed the name correctly, and then try again.

In Windows XP, you may see this error message:
Cannot find the file 'path ' (or one of its components). Make sure the path and filename are correct and that all required libraries are available.

There was a problem sending the command to the program.



Resolution: 
Turn off the "Ignore other applications that use Dynamic Data Exchange (DDE)“ setting

Microsoft Excel 2010 and 2013

Click the File tab, and then click Options.
Click Advanced, scroll down to the General section, and then clear the Ignore other applications that use Dynamic Data Exchange (DDE) check box in the General area.
Click OK.

Microsoft Excel 2007

Click the Microsoft Office Button, and then click Excel Options.
Click Advanced, and then clear the Ignore other applications that use Dynamic Data Exchange (DDE) check box in the General area.
Click OK.

Microsoft Excel 2003 or earlier versions of Excel

On the Tools menu, click Options.
Click the General tab.
Clear the Ignore other applications that use Dynamic Data Exchange (DDE) check box, and then click OK.

or 

use Microsoft Fix it



source: http://support.microsoft.com/kb/211494/en-us