Microsoft Windows LM / NTLMv1 Authentication Enabled
Medium Nessus Plugin ID 63478
The remote Windows host is configured to use an insecure authentication protocol.
The remote host is configured to attempt LM and/or NTLMv1 for outbound authentication. These protocols use weak encryption. A remote attacker who is able to read LM or NTLMv1 challenge and response packets could exploit this to get a user's LM or NTLM hash, which would allow an attacker to authenticate as that user.
Change the LmCompatibilityLevel setting to 3 or higher.