A 500-ICAP Communication Error response appears in a user's browser.
Use the following troubleshooting steps to diagnose the issue:
Examine the error response. The page contains the description of the error and additional details from the antivirus engine.
Examine the event log messages. If the ProxySG appliance is not able to establish a connection with the Content Analysis appliance, it logs the following message: Cannot establish a connection to service.
Examine the ProxySG appliance log files for the failure reasons. All file-scanning failures, such as timeout, file too big, and decompression errors, are logged here.