Windows Server - Setting LM and NTLM settings using Regedit

Asked By Aram Mirzadeh

18-May-10 12:42 PM

Hi,

I am having an issue sharing files between my three machines (there are
actually none windows machines as well using SMB share).

They all work with each other except "Windows 7" is misbehaving.
Everyone is prompted for a password to browse the 7 machine, and 7 is
asked for password when it tries to look at any other device.

This is obviously a "password encryption" thing that I have run into
before, but now I cannot seem to find a solution.

I have the following changes to Windows 7:

HKLM\SYSTEM\CurrentControlSet\Control\Lsa
LmCompatibilityLevel=1

Which I think is all I had to do with Vista and XP to get them to cooperate.

Since I do not have gpedit.msc, is there any other registery changes that
need to be made for this work?

Thank you.

18-May-10 09:31 PM

secpol.msc also has, under Security Options, Network Security: LAN
Manager Authentication Level ... which can make changes to the
setting.

registry:  HKLM/System/CurrentControlSet\Control\LSA  Look for the
0 = sent LM adn NTLM, never use NTLMv2
1 = use NTLMv2 if negitiated.  LM, NTLM and LTLMv2 can be used
2 = send NTLM only.
3 = sent NTLMv2 only.
4 = Domain controllers refuse LM.
5 = Domain controllers refuse LM and NTLM.

good luck.

Mike

19-May-10 09:24 AM

It does not look like 7 "Home" has secpol.msc either.  I tried setting
LmCompatiblityLevel to 0 and 1, neither seemed to work.

The only thing I notice is that LM vs Lm, but I do not think registry is
case sensative, but I will try it.

19-May-10 09:46 PM

The keys are not normally case sensitive.

Look here
http://www.howtogeek.com/howto/windows-7/share-files-and-printers-between-windows-7-and-xp/
and maybe
http://www.sevenforums.com/network-sharing/5369-networking-file-share-between-windows-7-windows-xp.html
to see if this helps any at all as well...

Good luck!!