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Cool things you can do with Office 2010
The Office Blog
Security Because macros can contain viruses, be careful about running them. Take the following precautions: run up-to-date antivirus software on your computer; set your macro security level to high; clear the Trust all installed add-ins and templates check box; use digital signatures; maintain a list of trusted publishers.
If you purchase, install, and activate a qualifying Microsoft Office 2007 product between March 5, 2010, and September 30, 2010, you could be eligible to download Office 2010 at no additional cost.