Best Answer Rob , 25 January 2013 - 02:41 AM
If you have a deprecated plugin, that could cause it. WordPress released an update today to 3.5.1. I'm unclear if they did something on the backend that might have affected plugins.
Instead of deactivating the plugins, let's make sure your permalinks are updated. Go to Dashboard > Settings > Permalinks and without changing anything, just Save.
That will update any links that may have become broken.
Next, I'd suggest going through each plugin and checking to make sure that they're all up compatible with WP 3.5.Go to the full post