Dear Eliezer, Unfortunately no success . I will describe what i did maybe i missed something . run the command perl -pi -e '$/=""; s/\r\n\r\n/\r\nX-SHMSCDN: HIT\r\n\r\n/;' /cache1/header/v1/* and verified that the text injected correctly squid config acl mshit rep_header X-SHMSCDN HIT clientside_tos 0x30 mshit but got the following popular log 2016/07/18 16:26:31.927 kid1| WARNING: mshit ACL is used in context without an HTTP response. Assuming mismatch. 2016/07/18 16:26:31.927 kid1| 28,3| Acl.cc(158) matches: checked: mshit = 0 One more thing . as i am not so familiar with perl , may i ask you to please edit it to ignore the files which already have the text ? Thanks -- View this message in context: http://squid-web-proxy-cache.1019090.n4.nabble.com/Windows-Updates-a-Caching-Stub-zone-A-windows-updates-store-tp4678454p4678557.html Sent from the Squid - Users mailing list archive at Nabble.com. _______________________________________________ squid-users mailing list squid-users@xxxxxxxxxxxxxxxxxxxxx http://lists.squid-cache.org/listinfo/squid-users