Proxy Access Control List

[croberti]

I want allow access only to some sites, so I enabled the "Transparent HTTP proxy" and I put this in WhiteList:
   
    http://mailserver.domain.it
    https://mailserver.domain.it

If I don't put anything in BlackList all works but users can navigate everywhere; if I put "." or "^." in Black list all other site are blocked but only the http site in WL works, the https return:

    The following error was encountered while trying to retrieve the URL: https://2.xx.xxx.xx/*

    Access Denied.

    Access control configuration prevents your request from being allowed at this time. Please contact your service provider if you feel this is incorrect.

why is this happening?

Bye, Claudio.