Is it possible to block HTTPS websites with the ASA 5505?
I have conflicting information.
Sorta... You cannot use the CSC modules on the ASA5505, all other ASA models can take that. It's required to do real HTTPS inspection (and thus blocking). However, you could configure an ACL on the 'inside' interface that disallows traffic to port 443, which could effectively cut off most HTTPS traffic.