Be aware when you follow the advice of "The LanMan authentication level will be set to Send NTLMv2 response only\refuse LM & NTLM." - If you change the value as recommended, you could run into trouble where you get this error message:
"Not enough server storage is available to process this command"
To fix this problem you must do as describe in this article by Microsoft:
But, do it before you do change the LanMan authentification level, because if you use RDP to access the server, you are lost in space if the error meets you when you try to log...