According to Microsoft article Q225511 titled, "New Password Change and Conflict Resolution Functionality in Windows"
By default, when a machine account password or user password is changed, or a domain controller receives a client authenticationrequest using an incorrect password, the Windows domain controller acting as the primary domain controller (PDC) Flexible Single Master Operation (FSMO) role owner for the Windows domain is contacted. This article describes a new registry value thatcan be used by the administrator to control when the PDC is contacted, which can help reduce communication costs between sites.
The following registry value can be modified to control Password Notification and Password Conflict Resolution as described below:
HKEY_LOCAL_MACHINE\System\CurrentControlSet\Services\Netlogon\Parameters
Registry value: AvoidPdcOnWan
Registry type: REG_DWORD
Registry value data: 0 (or value not present) or 1
0 or value not present = FALSE (to disable)
1 = TRUE (to enable)
Default: (value is not present)
Platform: Only Windows 2000 domain controllers
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