I am getting the following error when chaining qlproxy and squidclamav services. If I was to configure just qlproxy or just squidclamav service, it works. Note, this is a rare case as for the most part everything works fine. I am guessing because I hit mixed content (http and https). The configuration is below. ICAP protocol error. The system returned: (100004) Unknown error 100004 This means that some aspect of the ICAP communication failed. Some possible problems are: The ICAP server is not reachable. An Illegal response was received from the ICAP server. ------------------------------------------------------------------------------------------------------------- The squid config... icap_enable on icap_send_client_ip on icap_send_client_username on icap_client_username_encode off icap_client_username_header X-Authenticated-User icap_preview_enable on icap_preview_size 1024 icap_service_failure_limit -1 icap_service_revival_delay 30 icap_service qlproxy1 reqmod_precache bypass=0 icap://127.0.0.1:1344/reqmod icap_service qlproxy2 respmod_precache bypass=0 icap://127.0.0.1:1344/respmod icap_service squidclamav1 reqmod_precache bypass=0 icap://127.0.0.1:1345/squidclamav icap_service squidclamav2 respmod_precache bypass=0 icap://127.0.0.1:1345/squidclamav adaptation_service_chain svcRequest qlproxy1 squidclamav1 adaptation_service_chain svcResponse qlproxy2 squidclamav2 adaptation_access svcRequest allow all adaptation_access svcResponse allow all Thanks in advance