How to unlock a user account using the REST web api: https://rally1.rallydev.com/slm/webservice/v2.0/user/ObjectID
It is not possible to lock/unlock a user account using the API. Also, there is no option to reset a user's password. This functionality is performed by another system and the information for this is only displayed in our API. (IE: the "AccountLockedUntil" field is read-only).