To install PDF to DOC, simply run the MSI file. The MSI file will extract itself and automatically initiate the install procedure. If you are running Windows 98, ME, NT, or 2000, you may need to install the Microsoft Installer 2.0.

Windows 98 and ME users, you can download this free upgrade directly from Microsoft at:
http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=CEBBACD8-C094-4255-B702-DE3BB768148F

Windows 2000 and NT users, you can download this free upgrade directly from Microsoft at:
http://www.microsoft.com/downloads/details.aspx?displaylang=en&FamilyID=4B6140F9-2D36-4977-8FA1-6F8A0F5DCA8F

Windows XP users should have this installed by default, but if you do not, download and install the Windows 2000 version at the link listed above.