OK there are many ways you can check this:
1. Start by making sure that the normal notification is working correctly using "Database".
2. It is always good to looks at the server log.
3. In the SQL management studio - the table "DocumentActionInfo" need to be empty.
If you found that the rows are not removed verified the SMTP setup in the ePDM administration tool
These are the most common problems.
Let me know what you found and we can continue.
Now some of the searches are not working also?
We only use the database Inbox and not STMP.