My colleague Sean Daniel reminded me that in SBS SP1, we've enabled a new feature in Exchange SP1 to reduce the viability of performing a directory harvesting to get usernames on your SBS server. This feature (documented at http://support.microsoft.com...

Dan asked (a long time ago, sorry Dan) that he was getting notifications of accounts being locked out due to invalid password attempts. Dan's assuming this is because someone is trying to hack into an account and wanted to know how to stop SBS usernames...