Dec 07

Cannot Connect to Windows 7 SMB Shares from XP/2003

If you’ve ever tried connecting to a Windows 7 SMB share from a Windows XP or 2003 computer, you may notice you cannot connect to the server. Being the savvy person you are, you:

  1. Check the share and NTFS permissions on the Windows 7 Share
  2. Run gpresult on your XP/2003 machine and confirm you are a member of the correct groups
  3. Try connecting through start->Search and enter \\windows7 and get an error
    1. What! You cannot even see the server and it’s shares???
  4. You check the Windows 7 firewall and ensure file/print sharing is allowed
    1. It’s even enabled on the connected network (domain/home/public)
    2. Your IP subnet is even allowed
  5. You break out the command line and run net use z: \\windows7\share but get a System Error 58


The problem is Windows 7 uses NTLMv2 and XP/2003 use LM & NTLM.  To resolve this issue, do the following on the Windows 7 computer:

  1. Run GPedit.msc
  2. Expand Computer Configuration->Windows Settings->Security Settings->Local Policies->Security Options
  3. Open the properties for Network security: LAN Manager authentication level
    1. Set the value to: Send LM & NTLM – use NTLMv2 session if negotiated
  4. Run Services.msc
    1. Restart the Server service

You can now map your drive from your XP/2003 box to your Windows 7 computer!