If it is happening with more than one file, it sounds like a file association issue. For some reason Windows is treating DOCX files as if they are EXE or COM files.
Here is a selection of ways of fixing file associations:
Try repairing your Office installation, for example via Add or Remove Programs in Control Panel.
Repair or remove Office 2010 -
http://office.microsoft.com/en-us/excel-help/repair-or-remove-office-2010-HA010357402.aspx?CTT=1
Re-register the application
There are several different ways you can reset the proper file associations. Word itself provides a way to do it. Open a command prompt window and,
at the command line, enter the following:
winword /r
Nothing seems to happen when you press
Enter, but Word will reregister itself back in Windows. In the process, it resets the file associations for the files it uses, such as DOC and DOT files. You can close the command prompt window and double-click on a document; Word should start right
up.
Alternate Re-register the application
Close the app. Open the Run Window: <WIN> R, use the following command (Modify the Path to match your specific installation):
"C:\Program Files\Microsoft Office\Office\winword.exe" /unregserver
The quotes are necessary, but you may need to change the path so it reflects the location of the winword.exe file on your system. (You can use Windows’
Search tool to locate the path to the winword.exe file.) The /unregserver switch “unhooks” all the references to Word in the Windows Registry.
You should then, immediately, use the following command:
"C:\Program Files\Microsoft Office\Office\winword.exe" /regserver
This command causes Word to rewrite all its Registry keys and to reassociate itself with document and template files. Now you can double-click a document
file and see if Windows starts Word and opens the document.
Need to associate the file type with program:
In Windows 7:
- Right-click the file,
- Select "Open With" select [Your Program Here]
- Check always use this program.
Alternate method of associating file type with program:
- Click Start
- type cmd in the run dialog box then press ok.
- On the command prompt line type "control panel" without the quotation marks.
- In control panel > folder options > file types > new (button) in the new window click advanced.
- In the file extension dialog box type the file extension to fix, ie: exe.
- In the drop down menu locate and select application > click ok.
Sometimes one of these works when you're having trouble with double clicking on the file in windows explorer:
(xl2007) Office Button|Excel Options|Advanced|General|Uncheck "Ignore other applications that use DDE"
Change the program that opens a type of file -
http://windows.microsoft.com/en-US/windows-vista/Change-the-program-that-opens-a-type-of-file
Fix File Association Error When Launching Windows Explorer in Win7 -
http://www.winhelponline.com/blog/fix-file-association-error-explorer-in-windows-7/
How to Set Defaults Successfully
http://www.worldstart.com/how-to-set-defaults-successfully/print/
Win7 Set Default and Use Open With & Always Open With Settings in Pictures-
http://notebooks.com/2011/02/08/how-to-set-default-programs-and-use-open-with-and-always-open-with-settings/
RestoreEXE File Association in Windows 7/Vista After Incorrectly Associating It With Another Program -http://www.winhelponline.com/blog/restore-exe-file-asso-windows-7-vista-incorrectly-associated/
How To Change & Fix Broken File Type Associations In Windows 7 -
http://www.makeuseof.com/tag/change-fix-broken-file-type-associations-windows-7/
doubleclicking an individual excel 2010 file won't open it, can only open from the dropdown menu when office app is open-http://answers.microsoft.com/thread/2184f1b7-c13a-49a9-b1ed-f6a523d698cc
(You shouldn’t have to do this, but if nothing else works give it a try)