Wow, all the reading I did and NO ONE anywhere talked about or suggested this method. It's all about META tags that don't work or controlling cache with server configuration.
This is so simple and perfect, thanks falko you're a legend. How would you like to have a crack at my thread about getting a error 500 when I try to access Roundcube using mydomain.com/mailbox
Just quickly, I assume that this code goes in the <HEAD> section of your php page. Is this correct?
Oh, and where the above code sets the expiration date, can I use -1 rather than a date?