Microsoft Outlook 2007 cannot open an Excel file attachment

Hi,
I will have to specify my problem straight to the point. I have a problem with all of my Excel attachments whenever I am opening it in Microsoft Outlook 2007. My laptop is in Vista SP2. I can open Excel application fine. I can also open any attachments, but not Excel. This suddenly happened and no configurations was changed in my personal computer.
I have attempted to repair Microsoft Office and even reinstalled it because repair did not solve it. Unfortunately, reinstallation of Office will not resolve it either. I have also tried to focus on Excel. From Excel Options, I have changed the settings in Advanced, I have cleared the option, “Ignore other applications that use Dynamic Data Exchange (DDE)” and restarted Excel.
Techyv people, I need help.
