After upgrading to 3.1, found that a whole lot of posts do not show the "Edit | Quick Edit | Trash | Preview " links when you hover over the entry in the Posts section of the gui. The only link that shows is 'View', which when clicked on gives a 404 error. The title text is also black and unclickable (normally is blue as its meant to be a hyperlink).
Any ideas? I found one post here mentioning permalinks, but turning them off had no impact.
Edit: Found if I manually enter a URL to edit one of the affected posts, I get an error saying "You are not allowed to edit this item.". Comparing a working post and a non working post shows the same author id though.
Checked http://wordpress.org/support/topic/troubleshooting-wordpress-31-master-list, nothing there has changed anything
Setup a new copy of the site on a fresh install of WordPress. Problem followed - I suspect the issue is within the SQL DB.
The issue has been resolved.
The upgrade of WordPress went and changed my custom post type of 'For_Sale' to 'for_sale'. Any of the existing posts with the post_type of For_Sale then became unavailable to edit or view (though would still list in the admin gui and still could be queried).
Creating a new post would set Post_Type to for_sale and would be able to be edited/viewed/etc.
I ran an SQL query to change the case to all lower case on the affected posts, which has fixed the problem.
Detailed under http://wordpress.org/support/topic/31-rc3-uppercase-custom-post-type-problems?replies=15
planky