HP 6535b is not an operating system. I'd guess you have a computer manufactured by Hewlett Packard which would make this a windows system, most likely running Windows XP. If so, go to My Computer and right click it. Select Properties. The window that now appears will identify the operating system and also what service packs are installed. That's the info you should report as the Operating Sytem Version.
I also suggest that you click Edit POst and remove your phone number and email address. There are unscrupulous folks that can use software to scan web pages like these and "scrape" such personal info for use in spam and other such things. If Filemaker Inc or someone else needs to contact you privately, they can use the Private Message feature of this forum to contact you.
Thank you for your post.
Have you tried reinstalling FileMaker Pro? That is, uninstall and reinstall a fresh copy of FileMaker Pro 9. Then, use your file to see if anything has changed. Also, do you have a backup file prior to when the problems started? If your original file is damaged in some way, then revert to a copy that was working correctly.