Hello,

Yes in my delphi application I registered the event name

I tried POST_EVENT in a stored procedure but without DELETE FROM MON$ATTACHMENTS statement

sometimes it is fired sometimes not. I didn't understand why

When I write the event name like this : 

1-POST_EVENT 'DISCONNECT_USER';

It is fired

2-POST_EVENT 'DISCONNECT_USER]'||:USR; (I splitt the event name using "]" in the client in order to retrieve the event name part and the username part)

It is not fired

And when I back to 1 when it worked it is not fired at all 

Anyway I kept that idea of running POST_EVENT in SP and after waiting  I execute the delete statement.

I consider that my problem is solved

Thank you very much to all