Quote Originally Posted by amaginon View Post
I would like to know what "unusual access" to my account means.
The most common is logging in from an IP address which the system hasn't seen you log in from before. I don't know when SE's systems decide to flag it, I've had it once over a year ago when I changed ISPs, however just after launch I was using a VPN to get round ISP throttling and I didn't get hit.