How to Fix "Word experienced an error trying to open the file." error

if you are experiencing a problem in opening MS Office documents with this error:"Word experienced an error trying to open the file" or "Word has encountered a problem" while opening a document from your hard disk or Ms Outlook:

and if you have tried to open and repair the document but the error is still there, you will have to check the  "Protected view" settings in MS Office 2010 application..

Below are the steps..

1. Run one of the Office 2010 application (e.g. Word 2010).
2. Click on File menu, and select Options.
3. In the “Options” dialog, select Trust Center in the left pane.
4. Click on Trust Center Settings in the right pane.
5. Select Protected View in the left pane of “Trust Center” dialog.
6. Disable any of all of the protected view options as below by unticking the check boxes:
• Enable Protected View for files that fail validation
• Enable Protected View for files originating from the Internet
• Enable Protected View for files located in potentially unsafe locations
• Enable Protected View for Outlook attachments

Ref :
http://www.mydigitallife.info/2009/12/29/how-to-disable-read-only-protected-view-in-office-2010/