How do you Check file compatibility with earlier versions?
Check compatibility between your Microsoft Office 2010 files and
earlier versions of Microsoft Word 2010, Microsoft Excel 2010 and
Microsoft PowerPoint 2010, to check for features that are not
supported.
To save your file in an earlier format, see Save an Office file
as an earlier version.
Click the File tab.
Click Info.
Under Prepare for Sharing, click Check for Issues.
Select Check Compatibility. Any issues between the 2010 version
and earlier versions are listed in the Summary.
Note Selecting the Check compatibility when saving documents
check box automatically checks for compatibility issues when you
save your file as an earlier version.
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