1) Find out the computer that lockouts are originating from
Great tool from Microsoft to use is LockOutStatus [Account Lockout and Management Tools]
https://www.microsoft.com/en-us/download/details.aspx?id=18465
https://www.microsoft.com/en-us/download/details.aspx?id=18465
These tools are mainly for Windows XP and Server 2003, but LockOutStatus.exe works on Server 2008 R2 Active Directories.
