I am using a Windows 7 Pro 64-bit OS PC on a 2003 MS Active Directory network. I am getting random account lockouts which were initially all pre-authentication lockout failure audits. After a registry setting change to the OS to use AES encryption I still get the lockouts but they are more descriptive. The errors are 673 Failure Audits with SYSTEM listed as the user. However, the detail of the entry shows my AD user account and either cifs/servername or ldap/servername under Service Name. Ticket Options: 0x40810000 and failure code 0x12. Lockouts appear to happen no matter what DC I authenticate to. I am a domain admin but my user account is not added as a local admin on the PC. I have not been able to find out much info about this. Can someone please help me out? Thanks!