The ProxySG appliance's event log shows the following error messages when the appliance is acting as an SSL client communicating Blue Coat Heartbeats Daily statistics:
By default, after enabling email alerting, the ProxySG appliance starts to send Summary Statistics automatically on health updates once per day.
Refer to How to stop receiving "ProxySG Appliance Summary Statistics".
The error occurs because the ProxySG appliance is unable to communicate with Blue Coat Heartbeat server. It could be related to upstream devices, or the Heartbeat server may be down for maintenance.