Account_location question

I’m trying to setup subdomains using account keys (,, etc) and am using the account_location plugin. I’ve
got everything working properly. My only question is, how do I handle
invalid subdomains - for example, if I only have 2 accounts (user1 and
user2) and someone trys to visit

Right now the page just hangs and cannot be displayed. I’d like to
redirect them to login or provide an error message.