I am getting a very strange error in my IIS Log file. I am getting a sc-status of 500 for a couple CSS files and image files. There is no entry for the error message in the the cs-uri-query column. The pages display without error, and the styles and images display fine. This error occurs about 50% one of our pages is called, and about once a week on 5 other random pages. Each CSS file is used the same throughout each site on about 50 - 100 different pages.
<link REL="STYLESHEET" TYPE="text/css" HREF="default.css">