Windows 7 send lm ntlm

I went into the policies folder itself and looked at the. My policy that made everything work was set like this:. So there's a difference here and I'm not sure why the same security setting has different registry values.

Has anyone seen this or come across this before? So I discovered that the one of the values is designating which type of key to use maybe? Still uncertain as to how or why I think the behavior may be caused by the different OS between clients.

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Authentication to an Exchange server should work via Kerberos but if your forcing it with NTLM then you are setting yourself up for some future headaches, not to mention the one you are currently experiencing right now. That said, I think we need more information to figure out what's going on here. Namely, what is the OS version on the Outlook clients, the OS versions of the Exchange servers, the OS versions of the servers hosting Active Directory, the Active Directory domain functional level, and is Office involved here at all?

It wasn't me who kept it alive, but I do know the reason why. I found out we have an old proxy service that we are moving away from that when auto-passing authentication will only work when LM and NTLM responses is enabled.

My reason for the post was concerning what my group policy was doing. My default domain policy, when enabling this option as I stated above , the gpt. It's the policy that I'm more concerned with. But when that got changed to a REG string key, it was breaking connection to Outlook. Outlook would return the message that my server was offline and couldn't connect. When the key was a string, it broke the connection to exchange. Why that one option as a string when it's there, would tell Outlook that my Exchange server is offline and can't connect is beyond me.

I now know what the reason is and how to fix it, but what I don't understand is why my default domain policy decided to add it as a string while my other policies correctly create it with a DWORD value.

If anything, If a solution can't be found, I would at least like this to be informative to anyone else that may come up with a similar issue to be aware of this anomaly. Thanks for your clarification, it explains a lot. Furthermore, NTLM is grounded on three-way handshake between customer and server in order to authenticate customer while Kerberos rests on two-way procedure that is delivered by means of a ticket generating service or key distribution facility.

NTLM protocol was exposed before certain security risks and known security leaks or problems related to password hashing and salting. Such vulnerability could let attackers or online frauds crack password via multiple login attempts, and because of weak or trivial password, they could eventually manage to access the account.

In the first place, the domain administrator would like to be sure that NTLM and LM protocols are not permitted to be applied for authentication in domain. You can define the requested authentication method by means of the domain or local policy. Consider reading: Parental Controls in Windows Guide to Establish. In case the tutorial definitely helped you, then you can share the article with other customers to assist them.

Subscribe to our Telegram channel to be the first to know about news and our exclusive materials on information security. Japanese Spanish Chinese Traditional. Journalist, researcher, web content developer, grant proposal editor. Efficient and proficient on multiple platforms and in diverse media. Computer technology and security are my specialties. This choice affects the authentication protocol level that clients use, the session security level that the computers negotiate, and the authentication level that servers accept.

The following table identifies the policy settings, describes the setting, and identifies the security level used in the corresponding registry setting if you choose to use the registry to control this setting instead of the policy setting.

The following table lists the actual and effective default values for this policy. Changes to this policy become effective without a computer restart when they are saved locally or distributed through Group Policy. Modifying this setting may affect compatibility with client computers, services, and applications.

This section describes how an attacker might exploit a feature or its configuration, how to implement the countermeasure, and the possible negative consequences of countermeasure implementation.

In Windows 7 and Windows Vista, this setting is undefined. The default setting on servers allows all client computers to authenticate with servers and use their resources. However, this means that LM responses—the weakest form of authentication response—are sent over the network, and it is potentially possible for attackers to intercept that traffic to reproduce the user's password more easily.