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How to Open thmx File?
http://www.vistaarticles.com/articles/431/1/How-to-Open-thmx-File%3F
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Published on 05/20/2007
 
Office theme File.

How to Open thmx File?

Format used in Microsoft PowerPoint 2007. To use earlier versions of Microsoft PowerPoint to open files from PowerPoint 2007 download Compatibility Pack.

Download Free Compatibility Pack from Microsoft:
http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=941b3470-3ae9-4aee-8f43-c6bb74cd1466