Using older/weaker authentication levels (LM & NTLM) make it potentially possible for attackers to sniff that traffic to more easily reproduce the user's password.
Option 1- Set the following Group Policy: Computer Configuration\Policies\Windows Settings\Security Settings\
Local Policies\Security Options\Network security\
LAN Manager authentication level To the following value:
Send NTLMv2 response only. Refuse LM & NTLM
Option 2 - Set the following registry value: HKLM\SYSTEM\CurrentControlSet\Control\Lsa\
LmCompatibilityLevel To the following REG_DWORD value: 5