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Unable to connect to Windows from Mac via SMB

Unable to connect to a Windows SBS 2003 server from Mac (10.6.4)

The error pop-up says: connection failed. check the server name or IP address. -i have as i can connect to OWA with this address.

Attached is a screen cap of the error message and a cap of the terminal. Can someone help?
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1 Solution
What is your Windows version ?
If it's a Vista or 7 or Server 2008 This Windows uses NTLMv2 only protocol for authentication.
MacOsX relie on Samba for susch connection and Samba can't handle NTLMv2.

Their is a trick to force Windows to accept either NTLMv1 or NTLMv2

Try this in registry ( Widnows Menu / Run / regedit )

1. Run the registry editor and open this key:


1. If it doesn't already exist, create a DWORD value named

3. Set the value to 1

4. Reboot
LuxtechAuthor Commented:
this is sbs 2003 sp2. i found the key and it was set to (2). i have changed this and will schedule a reboot tonight.
Is it prompting you to authenticate at all during this process?  Are you able to browse to the share and connect or are you using connect to server?  What is the syntax you are using? Im assuming you can ping it?  might also check the firewall on the server to see if it might be blocking access.  
LuxtechAuthor Commented:
I am using finder/connect computer with the following syntax smb://servername (have also tried smb://serverIP)I I can definately pint it. I can also telnet on port 445. It asks for username and password. I am using the correct credentials because if i get them wrong i get a bad username/password error instead.
Im curious.  Try changing the TCP acknowledgment.  

Easiest way to do it is the use this startup item.


If that has no effect, just uninstall it.  You can also try making the change on the server.


I have seen this change make a dramatic difference in speed from Mac clients to Windows servers.  
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