I have read the FAQs and checked for similar issues: YES
My site's URL (web address) is: http://www.tsia.com/about_us/press_releases/2010_press_releases/2010_06_new_fs_member.html
Description (including timeline of any changes made):
I am using ISAPI rewrite and MODx CMS.  I have not made any changes to my rewrite conditions recently.  This error just appeared over the long weekend and I am 100% positive no changes where made to the site during this time.

Previous when my rewrite conditions where wrong, I was getting 500 status codes.  But I fixed that and Googlebot was returning my pages.

Anyone have any clue as to why Fiddler returns a 200 while Googlebot is saying status not found.

Thanks,

Jason Buck
TSIA