The document could not be opened for editing in SP 2010 with MS Office Professional Plus 2010 64-bit

Dear All, 

I am working on Sharepoint Foundation 2010 on Windows 7 64-bit; 
I have a Sharepoint site with document library. 
upload Microsoft word documents, when I select one of them and click on "Edit in Microsoft Word" then I got an ERROR 
"The document could not be opened for editing. A Microsoft SharePoint Foundation compatible application could not be found to edit the document. " 
I have already installed MS Office Professional Plus 2010 64-bit on my machine.. 

Please let me know what is the problem and how to resolve this... 

I am waiting your valuable reply. 

Thanks & Regards