When you write a new key, or Value Name, or change / delete a Value Name, Windows records the data time in the registry key.

To view the Last Write Time for a key and sub-keys, use REGEDIT.EXE to select the key, right-click it, and press Export. Toggle the Save as type box to Test Files (.txt). Navigate to a folder and type the file name into File name. Press the Save button.

When you open the file in NOTEPAD.EXE, each key in the file has a Last Write Time attribute.

Sample:

Key Name:          HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\lanmanserver
Class Name:        <no class>
Last Write Time:   01/28/2006 - 04:06
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