Mike, I went to the install and clicked the "Rebuild Master Data" button and that fixed it...thanks
I have a question though...Before I posted here I thought it may have been a corrupt file so I uploaded the entire Library folder again but that didn't fix it so I did as you advised which did fix it...the question is does doing these two things effect my installation in any way like file permissions, overriding any options, settings or any changes that I have made to the site?