@mike L & @elias
I’ve no answer with this error. So I decided to downgrade my WP 3.5 to the previous version (3.4.2). How i do that..? i just replace all files in my hosting except wp-content folder with my back-up files (in 3.4.2 version)
If you don’t have a backup of your web files, many hosting provider have a daily n weekly backup. So You can ask them to rollback your files.
Hope it help. ??