Some users have reported that in certain conditions it is impossible to reconnect to a SilverSHielD server after an abnormal client disconnection. Up to version 220.127.116.11 there was a bug that prevented SilverSHielD to handle abnormal client disconnections properly.
This was particularly apparent in the Free version of SilverSHielD because it's limited to a single client connection and thus, when such client connection gets "broken", no more clients were allowed to connect and - de facto - SilverSHielD stopped working.
Anyway such strange behavior happened only when a client suddenly disconnected without sending the proper command to close the SSH channel (as it is supposed to do).
EASY FIX: update/upgrade SilverSHielD to the latest version will solve the issue (actually fixed in 18.104.22.168).