Windows 7 connecting to Domain Controller Unknown Login Error

I've setup a windows dual boot system with Windows XP professional and Windows 7 professional x64 on a Dell Optiplex 740. The windows XP was installed on an 80 GB 10K disk and the windows 7 professional x64 partition was setup on an Intel SSD drive. Both installations were done from scratch (no imaging).

Right now The system running windows 7 professional x64 on the SSD is having problems connecting to my Domain controllers (Windows server 2003 x64 sp2 - fully patched). When I first did the install of the operating system and was doing the software installation from our network I didn't have any problems. However After setting up the system for our Developer and moving it about 150 feet down the hall, this windows 7 system has a problem logging on to our network.

The error message I get after trying to login is is Unknown logon Error.

I have tried different network cards, a completely different network port, updating drivers and none of this has resolved my issue. I have removed the system from the domain and re-added it and this worked for roughly 24-36 hours. Then the developer mentioned they were having the same login problems as before.

This issue occurs with the developers credentials as well as a the credentials from a Domain Administrator.

The XP system and windows 7 system are named similarly, but they are still different. Both systems are using the same dns servers. Currently I don't see any error messages on either my domain controller or the windows 7 system.

If I trick the computer into using cached credentials, I can login to the Windows 7 system. After connecting the network cable I'm able to ping the domain controllers, do a nslookup of our domain and get to the Sysvol folders on the domain controllers. After restarting the system, Sometimes it I can login without using the cached credentials but more often then not it cannot.

Any ideas on how to get this Windows 7 system to work properly within our domain?

The windows XP system doesn't have any problems. It is able to login without issue. I have done a similar setup to the one listed above, but the windows 7 partition is on another 10K drive not an SSD. This one doesn't have any problems.

Thank you for your help.

Have you tried working with the lanman server perimeters in the GPO of the Windows 7 machines?

In order for Windows 7 to work with older servers you usually need to adjust the lanman server security settings.

The following settings may help.

Control Panel - Administrative Tools - Local Security Policy

Local Policies - Security Options

Network security: LAN Manager authentication level
Set to Send LM & NTLM responses only

Set the Minimum session security for NTLM SSP
Disable Require 128-bit encryption

Thank you for your help Chev65, but that did not resolve my issue.

All in all my issue comes down to this 1 windows 7 professional system cannot communicate with the domain controllers while logging in. I tried the change and did the gpupdate on that workstation and I still got the error : Unknown logon error has occurred.

The odd thing is I'm prompted for credentials every time I have added and removed this workstation from the domain. For the time being I have disabled all of the windows firewalls.

Hi 2XG,

I've verified the DNS settings and the Domain name and everything is correct.

The only thing I can think of is the communication between the windows 7x64 system and the windows server 2003 standard SP2 domain controller.

Do you know if there is a registry setting in Windows 7 for the communication time (for active directory) between the local system and the Domain controller? I know in Windows XP there was a setting that you could change to allow more or less time for the system to attempt communication to the DC.

Thank you.

Without some more specific error messages I can only guess what the problem might be.

This link may be helpful, I realize you know what your doing but it shows some details in order to join a Domain from a Windows 7 machine including some rather specific DNS settings.
Join a Domain in Windows 7

The only other problem I can find might be because this same machine had a Domain account with XP before it was turned into a Windows 7 machine, the link below shows a way to fix that type of problem.
How to Repair Windows Cannot Connect to the Domain Errors

I don't have a DHCP server setup. I only use static IP addresses on our networks.

As for a more specific error message I wish I could give one. While logging into windows after entering the user name and password I get the unknown logon error has occurred and that's it.

I will look at the links that Chev65 provided and see if they help. I'll post my results later (depending on my workload the post may not occur until monday).

Thank you for your help.

I think I have resolved my issue. I looked over the links that Chev65 provided me and they are very good links, but they didn't help me to resolve my issue. After this point in time I decided to reformat that partition and rebuild the windows seven system. However I did find out some information about the issue from before.

I had found out that originally when the computer was first installed the first installer had created a local user with the same name as the domain user for the initial administrator user (call it jsmith). Then after this system was joined to the domain, the jsmith user was deleted and the jsmith domain user was logged into the system. This is when I took over the installation. I installed all of the software under the domain administrator and then we moved the computer to the cubicle for the new developer. Then jsmith logged in and we stared having problems. I believe that somewhere within the registry and/or some configuration files there was some corruption and the local user jsmith still existed with an entirely different password. Then when the domain jsmith user would try and login, the system would be confused about which jsmtih user to then the user wouldn't have been able to login. This doesn't fully explain the issues I experienced with the domain administrator not being able to login properly either, but as of right now, the new system is working.

Chev65 and 2xg I appreciate your help with this matter. Thank you!