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SDR NTLM Authentication Version?

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I found this article showing that at least older versions of Backup Exec system recovery disk uses NTLM v2 but in my expereince testing SDR in Backup Exec 2012 I could only get the SDR session to log in if I reset my domain controller to use NTLM v1 authentication. Is there something that I haven't configured correctly or is this just the way it is? The security requirements of my system require me to use NTLM v2 only. 


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...this looks to be quite a technical question so I have hit the support flag.


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By default SDR uses the following settings


               LmCompatibilityLevel value of 1: Use NTLMv2 session security, if negotiated. Clients use LM and NTLM authentication, and use NTLMv2 session security if the server supports it; domain controllers accept LM, NTLM, and NTLMv2 authentication.


Warning: Incorrect use of the Windows registry editor may prevent the operating system from functioning properly. Great care should be taken when making changes to a Windows registry. Registry modifications should only be carried-out by persons experienced in the use of the registry editor application. It is recommended that a complete backup of the registry and workstation be made prior to making any registry changes.

If you want to change this authentication level, you have two options.


  • When you are in the SDR mode (booted off SDR DVD), before installing network, open a command prompt to run regedit.exe and change the value of the registry key ‘HKEY_LOCAL_MACHINE\System\CurrentControlSet\Control\LMCompatibilityLevel’ to the desired settings. See the Microsoft KB article that explains the full range of values for the ‘LMCompatibilityLevel’ key.


  • If you want to change this permanently for all of your SDR recovery images, then change the value of ‘LMCompatibilityLevel’ in the following configuration files on your media server and recreate the SDR recovery CD.


                              <BackupExec Install Path>\SDR\win32\Configuration\HKLM.System.reg

                              <BackupExec Install Path>\SDR\win64-x64\Configuration\HKLM.System.reg