SOLVED!!!!!! FOR ANYONE HAVING SAME ISSUES , FOLLOWS COMPLETE SOLUTION NOW Step 1 : /etc/init.d/squid stop STEP 2 : ( which I think should be solved by SQUID in a next update cause this could be categorized as a bug ) Delete fiels in /var/lib/ssl_db/certs , then empty index.txt and change number in size file to 0 This must be done because if SQUID generated for your sites Certificates using some other Certificates, it WONT BE OVERWRITTEN If you change to a new certificate. Example you generated www.grc.com certificate with a previous certificate then u changed to some Other certificate and continued with it ... www.grc.com certificate is kept with old info , which in turn causes problems later on. ( this could happen to you if you don't succeed at setting it up at first and play around with certificates, or for example your certificate expires And you need to issue a new one ) DON'T FORGE if you change the CERTIFICATE in SQUID empty /var/lib/ssl_db/certs and index.txt and size to 0 , otherwise it wont work @!#!@#!@ STEP 3: I created certificates this way because it is a lot simplier : Cd /etc/squid/ssl_cert openssl req -new -newkey rsa:1024 -days 1365 -nodes -x509 -keyout myca.pem -out myca.pem ( this is for squid ) openssl x509 -in myca.pem -outform DER -out myca.der ( for Windows XP in this case ) STEP 4 : Alter squid conf (my previous on only this line ) https_port 3129 intercept ssl-bump generate-host-certificates=on dynamic_cert_mem_cache_size=4MB cert=/etc/squid/ssl_cert/myca.pem key=/etc/squid/ssl_cert/myca.pem STEP 5 : Move mycert.der to WindowsXP client and add it to root trusted certificates I just tested : It works on my Cent OS 6.5 box with SQUID 3.4.3-1.el6 with Firefox, Internet Explorer, and Chrome NOTE : Chrome seems to use the same certificate store as IE, but you still need to add in IE as well. Remember : everywhere To root trusted sertificates and viola, it works! STEP 6 : Someone should do something about squid somehow checking if existing keys in /var/lib/ssl_db match with new certificates , I don't know How this generation works, but I guess It (could?) be possible to remove invalid certificates ? Greetings Robert Ps.; I'm so happpyyyyy : )