Thank you for your post.
Although FileMaker Pro 9 was not tested with Windows 7 (see Knowledge Base Article #7453 (http://filemaker.custhelp.com/cgi-bin/filemaker.cfg/php/enduser/std_adp.php?p_faqid=7453), some users appear to be using it. If you are having difficulty installing, please contact our Technical Support department at toll-free 800-325-2747. If you are located outside of North America, go to our web site (www.filemaker.com) and select "Worldwide Sites" in the upper right corner and find the office nearest you.
Have you tried running the installer as an administrator.
By which I mean, right clicking on the installer file (setup.exe) and choosing run as administrator, not just relying on your windows log in being an admin account.
Also, do you have User Account Control (UAC) enabled ?
Although this didnt cause an issue for me, may be worth turning it off for the install.
Disabling the UAC b4 install worked like a charm. Thanks!!