Abstract: An authentication process receives information identifying a user, a device used by the user and a location in which the device is being used. That authentication process determines whether the location is among a set of familiar locations stored about the user for a service being accessed. If the location is not among the set of familiar locations, then the user is not authenticated. A desirable user experience can be obtained by using information about any existing relationship, such as a synchronization relationship, between the device and the service established at a prior familiar location. Instead of challenging a user whose device is in an unfamiliar location, the authentication process determines whether the device has a relationship established with the service. If the device has a relationship established with the service, then the set of familiar locations is updated to include the location in which the device is being used.

Abstract: The claimed subject matter provides a method for detecting compromised accounts. The method includes receiving a communication from a sender's account to a recipient. The sender's account is associated with a sender. The method also includes presenting a compromised account reporting interface to the recipient based on specific conditions. Further, the method includes receiving a selection by the recipient indicating the sender's account is compromised. The method also includes determining that the sender's account is compromised based on the selection. Additionally, the method includes generating, in response to a selection by the recipient, a report indicating that the account is compromised.

Abstract: An authentication process receives information identifying a user, a device used by the user and a location in which the device is being used. That authentication process determines whether the location is among a set of familiar locations stored about the user for a service being accessed. If the location is not among the set of familiar locations, then the user is not authenticated. A desirable user experience can be obtained by using information about any existing relationship, such as a synchronization relationship, between the device and the service established at a prior familiar location. Instead of challenging a user whose device is in an unfamiliar location, the authentication process determines whether the device has a relationship established with the service. If the device has a relationship established with the service, then the set of familiar locations is updated to include the location in which the device is being used.

Abstract: The claimed subject matter provides a method for detecting compromised accounts. The method includes receiving a communication from a sender's account to a recipient. The sender's account is associated with a sender. The method also includes presenting a compromised account reporting interface to the recipient based on specific conditions. Further, the method includes receiving a selection by the recipient indicating the sender's account is compromised. The method also includes determining that the sender's account is compromised based on the selection. Additionally, the method includes generating, in response to a selection by the recipient, a report indicating that the account is compromised.