How to Configure NTLM Authentication
- 1). Click the Windows "Start" button and select "Run." Enter "regedit" into the text box and press "OK." The Windows registry editor opens.
- 2). Double-click the Windows registry keys until you reach the "HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control" directory. In the window area on the right is the detail page for this registry key.
- 3). Right-click the white space in the details section and select "Add Value." In the text box labeled "Value Name," enter "LMCompatibility."
- 4). Select "REG_DWORD" from the drop-down list of options. In the text box labeled "value," enter "3". The value "3" sets the machine for the highest level of NTLM authentication.
- 5). Press the "OK" button to save the settings. Reboot the Windows machine. Changes to the Windows registry do not take effect until the machine is reboot.
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