If you find that you are not able to open an Word 2010, Excel 2010, or PowerPoint 2010 file from the Internet or in some cases Outlook, and you get an error message, performing the following steps will resolve the issue:
Office 2010 may report the file as being corrupt. The exact Errors may include:
Word: Word Experienced an error trying to open the file.:
Excel: The file is corrupted and cannot be opened.
PowerPoint: PowerPoint found a problem with content in file. PowerPoint can attempt to repair the presentation.
The following steps will set component security settings back to the defaults.
Open Control Panel
Open Administrative Tools
Open Component Services and expand the tree under Console Root to Computers > My Computer.
Right-click on My Computer and select Properties.
Select the Default Properties tab and set the following values:
Default Authentication Level: Connect
Default Impersonation Level: Identify.