logon failure: unknown user name or bad password. Windows 7 machine trying to connect to Vista

Question

I have bought a W7 PC and am trying to log on to other PCs on the network. I can connect to one, can't connect to the other but can see them both in the network and sharing centre/view network computers and devices. When I try to log into the non-connecting device, the system automatically changes the user ID - I'm on ADMIN, trying to connect to GUEST - it changes my sign in from GUEST to ADMIN_PC\GUEST.

I connect to the LAN from the W7 machine wirelessly. The Vista machine I can log onto is connected via ethernet link to the router. The machine I can see but cannot log into is connected to a switch via ethernet and then connected via ethernet to the router. 

Having read discussion boards, it looks like this problem can be fixed by making changes to Local Security Policy - Network security: LAN Manager authentication level but I cannot find where to do this.

I am at the end of my thether - I believed the hype and thought that W7 would be easy to use. What do I have to do to get this thing to work?

Answer 1

You don't need to change anything with LAN Manager. The problem is probably related to Item C below. Here are general network troubleshooting steps. Not everything may be applicable to your situation, so just take the bits that are. It may look daunting, but if you follow the steps at the links and suggestions below systematically and calmly, you will have no difficulty in setting up your sharing.

Problems sharing files between computers on a network are generally caused by 1) a misconfigured firewall or overlooked firewall (including a stateful firewall in a VPN); or 2) inadvertently running two firewalls such as the built-in Windows Firewall and a third-party firewall; and/or 3) not having identical user accounts and passwords on all Workgroup machines; 4) trying to create shares where the operating system does not permit it.

In Windows 7, go to Control Panel>All Control Panel Items>Network and Sharing Center. Click on "Change advanced sharing settings". You don't want to use Homegroup unless you have all Windows 7 machines. If you do and you want to use Homegroup, see Windows 7's Help & Support. Otherwise, in the Advanced Sharing:

Turn ON network discovery

Turn ON file and printer sharing

Turn ON sharing in the Public folder sharing section

Turn ON password protected sharing

A. Configure firewalls on all machines to allow the Local Area Network (LAN) traffic as trusted. With Windows Firewall, turning on Window's File and Printer Sharing as above will take care of this for you. In XP you can run the Network Setup Wizard or just enable File/Printer Sharing in the Windows XP Firewall's exceptions. If you aren't running a third-party firewall or have an antivirus/security program with its own firewall component, then you're fine.  With third-party firewalls, I usually configure the LAN allowance with an IP range. Ex. would be 192.168.1.0-192.168.1.254. Obviously you would substitute your correct subnet. Refer to any third party security program's Help or user forums for how to properly configure its firewall. Do not run more than one firewall. DO NOT TURN OFF FIREWALLS; CONFIGURE THEM CORRECTLY.

B. For ease of organization, put all computers in the same Workgroup. This is done from the System applet in Control Panel, Computer Name tab.

C. Create matching user accounts and passwords on all machines. You do not need to be logged into the same account on all machines and the passwords assigned to each user account can be different; the accounts/passwords just need to exist and match on all machines. DO NOT NEGLECT TO CREATE PASSWORDS, EVEN IF ONLY SIMPLE ONES . If you wish a machine to boot directly to the Desktop (into one particular user's account) for convenience, you can do this:

Start>Search box>type: netplwiz [enter]

Click on Continue (or supply an administrator's password) when prompted by UAC

Uncheck the option "Users must enter a user name and password to use this computer". Select a user account to automatically log on by clicking on the desired account to highlight it and then hit OK. Enter the correct password for that user account (if there is one) when prompted. Leave it blank if there is no password (null).

XP - Configure Windows to Automatically Login (MVP Ramesh) - http://windowsxp.mvps.org/Autologon.htm

D. If one or more of the computers on your network is XP Pro or Media Center, turn off Simple File Sharing (Folder Options>View tab).

E. Create shares as desired. In Windows 7 I usually share out the user's Desktop and the Public directory.

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MS-MVP - Elephant Boy Computers - Don't Panic!

Answer 2

Ok, after numerous failures to determine the cause for login failure, I think I finally found the culprit.  I've gone into several computers which our log management system has reported as a device the attempted logon originated from.  I've removed all user accounts by the name of the "Target User Name" and I've looked at task manager on all systems and could not find any events running with that user account name.  After searching multiple locations, I went into the Task Scheduler and started looking for any tasks scheduled to run within the time frame of when I've seen the failed login attempts.  The one I found, needle in a haystack, was the "User_Feed_Synchronization" feed.  This feed was running at the same time of the failed login and it had the user account I've been hunting for running the task.  I disabled the task and I haven't seen the failed login return.

Hope that helps.