Do these steps in this link…
http://forum.ait-pro.com/forums/topic/plugins-have-disappeared-after-updating/#post-14432
….and then do these steps to restore whichever files need to be restored from Quarantine. You can delete any BPS Pro plugin files that are in Quarantine and do not need to restore them.
http://forum.ait-pro.com/forums/topic/plugins-have-disappeared-after-updating/#post-14172