Apache2 ServerTokens directive not working (Apache version still appear). How to fix it?

Apache2 ServerTokens directive not working (Apache version still appear). How to fix it? References I\'m using Ubuntu server 12.04 LTS with Apache 2.2.22 installed on it. I want to hide Apache version for better security. I tried this in /etc/apache2/conf.d/security: ServerTokens Prod ServerSignature Off After reloading Apache, the server still print its version : Apache2 / 2.2.22 (Ubuntu). No other same directives exist in other files somewhere else in the system. How can I debug/fix this ? Many thanks