Hello, I've sent this message a few days ago but got no reply yet. Should i try it somewhere else? ----------------- I get random DENIEDs, but do not find the cause of it. Config: external_acl_type simpleheaderauth ttl=600 concurrency=500 children=1 %>{Proxy-Authorization} mono /opt/squidhelpers/authhelper.exe simpleauth acl simpleheaderauth_passed external simpleheaderauth http_access allow simpleheaderauth_passed Log: ------ 2012/10/02 20:06:40.901| aclmatchAclList: async=0 nodeMatched=0 async_in_progress=0 lastACLResult() = 0 finished() = 0 2012/10/02 20:06:40.901| ACLChecklist::preCheck: 0x7f703fbe1178 checking 'http_access allow simpleheaderauth_passed' 2012/10/02 20:06:40.901| ACLList::matches: checking simpleheaderauth_passed 2012/10/02 20:06:40.901| ACL::checklistMatches: checking 'simpleheaderauth_passed' 2012/10/02 20:06:40.901| ACL::ChecklistMatches: result for 'simpleheaderauth_passed' is -1 2012/10/02 20:06:40.901| ACLList::matches: result is false 2012/10/02 20:06:40.901| aclmatchAclList: 0x7f703fbe1178 returning false (AND list entry failed to match) 2012/10/02 20:06:40.901| ACL::FindByName 'simpleheaderauth_passed' 2012/10/02 20:06:40.901| ACLChecklist::asyncInProgress: 0x7f703fbe1178 async set to 1 2012/10/02 20:06:40.901| ACLChecklist::asyncInProgress: 0x7f703fbe1178 async set to 0 2012/10/02 20:06:40.901| aclmatchAclList: async=1 nodeMatched=0 async_in_progress=0 lastACLResult() = 0 finished() = 0 2012/10/02 20:06:40.902| ACLChecklist::preCheck: 0x7f703fbe1178 checking 'http_access deny all' ----- With successful requests, i get a result "-1", and shortly after that a similar log output with result "1". With failed requests, i only get a "-1". The My auth helper log says that the request was answered successfully. Any ideas what the problem can be? If not, where else should i look for the problem? # squid -v Squid Cache: Version 3.1.20 Best Regards Nils Hügelmann