WhenChanged is an attribute in Microsoft Active Directory and is the date when this object was last changed.

WhenChanged value is not replicated and exists in the Global Catalog.

modifyTimestamp is marked as Constructed Attribute (effectively an alias for whenChanged) [1]

WhenChanged is marked "NOT REPLICATED(1)" which will require the application to query all DCs in the Domain for most recent value when comparing the attribute and security stamp.

LDAP Microsoft Active Directory Attribute Definition#

The WhenChanged AttributeTypes is defined as:

More Information#

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