Here's the Setup: 3 PC's, wired network, using Linksys WRT54G router, this has wireless function not used. PC#1 is running Win7 Pro. Password protection on shared folders is turned OFF. No shared folders. There is only one account on this PC and no accounts which match the accounts on PC#2 or PC#3 as it is not required by Win7 when Shared folder password protection is turned off. PC#2 is running Win2000 Pro. 2 shared folders. There is a user account on this machine which matches the one on PC#1 as Win2000 doesn't do simple file sharing. There is NO account on this machine which matches PC#3. This machine acts essentially as a data server to the other two PC's for documents, etc. PC#3 is running Win2000 Pro. 1 shared folder. There is a user account on this machine which matches the one on PC#1 and an account which matches the one on PC#2 as Win2000 doesn't do simple file sharing. Regarding firewalling, all 3 PC's are running Zonealarm and a trusted zone is created with a range of IP addresses which includes the assigned IP addresses of these 3 PC's. Everything was working fine.... PC#1 could access PC#2's shared folders through Windows Explorer, an application or by mapping in the share as a drive. PC#3 could access PC#2 shares as well, same as with PC#1. PC#2 doesn't need to access either of the other PC's. 2 days ago the LAN was breached, on the unused wireless side by a rogue PC (unknown origin). Linksys router was reset to factory defaults and re-programmed as to the SSID, Wireless P/W and Router Setup P/W to keep out the offender. The WORKGROUP name was changed on all 3 PC's and it matches the new SSID. No PC User Account Names or P/W's were changed, however, in attempt to resolve problems the user account for PC#1 was re-established on PC#2. Currently, all the PC's can see each other in their "Network" or "My Network Places" respectively. The 2 Win2000 Pro PC's are communicating fine. PC#1 can see the 2 Win2000 PC's but any attempts to access those PC's (clicking on the respective PC in Windows Explorer) results in: ENTER NETWORK PASSWORD request. Curiously, the box lists a reference to a "Domain" and list the name of PC#1 and the User Name of that PC. All 3 PC's are set to WORGROUP's not DOMAIN setting as this is a peer to peer LAN. Multiple hours and re-checking of settings has resulted in no luck in resolution of the problem. At my wits end. After 20 years as a VAR, can't figure this one out...Something got changed or reset, perhaps by the rogue PC that breached the LAN from the wireless side. No reason to believe that he not just riding the wireless free connection. No other damage perceived to any of the 3 PC's. Would appreciate any ideas or solutions. Regards, Gregory J Prokopp, Microsoft Partner

I hate zone alarm, I like Microsoft Security Essentials, link on my developer and IT sites. Now as for the server, I assume the share was a public share My MVP is for the Windows Desktop Experience, i.e. Windows XP, Vista and Windows 7 IT Remote Assistance is available for a fee. I am best with C++ and I am learning C# using Visual Studio 2010 Developer | Windows IT | Chess | Economics | Hardcore Games | Vegan Advocate | PC Reviews

Shared folder is on PC#2 and is accessible by anyone on the Local LAN. Tried Shutting down Zonealarm on all the machines.....No Effect, so, it's not Zonealarm causing the problem. New development....... Attached (wired) a notebook with Win7 64 bit (just like PC#1) last night as a test. Had configured that Notebook to look just like PC#1, that is, Same Workgroup name and same user account. Got the same result noted in the primary thread. To me that ruled out the PC itself (PC#1) as somehow corrupted. This morning replaced the router it self (Bought a new Netgear N300) and configured it into the system as was the Linksys WRT54G....Thought maybe the router went over the edge....... Nothing changed. Lastly, this morning I tried to access the public document folders on PC#1 from PC#2 (running Win2000), in other words, the reverse of the problem connection, and accessed PC#1 with no problem. Conclusion.....I feel I have ruled out PC#1 as corrupted, ruled out the Router itself. Now I have only one conclusion left...... Wonder if there was a security update to Win7 64 bit edition which somehow is interferring with communication with a lowly Win2000 machine??? As the whole working LAN developed this problem litterly from one day to the next and there is no sign the unknown guy who attached wirelessly to the router did anything but ride the bandwith, this is all I have left. I can't come up with another conclusion as I have apparently hit a wall on this one again.

There are a host of reasons why access may be denied. I had exactly same symptoms as you describe, same workgroup same user accounts etc Win7 machine not abe to access files on Win XP machine but vice versa was OK In my case fix was achieved in gpedit.msc on Win XP machine Local computer policy - Windows settings - Security settings - Local policies - User Rights Assignment - Deny access to thus computer from the network In that seting, remove Guest from ths list of denied users. That should eliminate the call for network password on the Windows 7 machine and allow annonymous access (if all other permissions OK!) This security setting determines which users are prevented from accessing a computer over the network. This policy setting supersedes the Access this computer from the network policy setting if a user account is subject to both policies.

Ok, Good suggestion, will try that next...Won't be able to try on system in question until tomorrow......

Tried above solution, Guest account was not denied. Again, no resolution. Have decided to upgrade Win2k machines to XP. Test with borrowed XP machine proved the problem is solved by eliminating Win2k. Does seem like one of the Microsoft Update upgrade/patches to Win7 64 bit machine caused the problem to appear overnight. Nothing else changed.... Consider this matte closed, gave up.

As with you Gregory, I spent many hours at the beginning of March trying to figure out why my Win7 Pro workstations quit connecting to my Win2000 server. I tried many different things, removing accounts, resetting passwords, creating new accounts and nothing worked. I found that by going clicking on the clock in Win7, clicking change date and time settings, clicking change time zone, uncheck "Automatically adjust clock for daylight savings time", clicking OK, click change date and time and putting the hour to the correct hour that this resolved my problem. It would seem that the daylight savings time feature in Win7 is causing problems. I am no expert in how Windows writes their code, but I think they should look at this and fix it. Hope this helps you as it has helped me. Regards, Victor Dacey

Windows 2000 is now no longer supported, get a new server My MVP is for the Windows Desktop Experience, i.e. Windows XP, Vista and Windows 7 IT Remote Assistance is available for a fee. I am best with C++ and I am learning C# using Visual Studio 2010 Developer | Windows IT | Chess | Economics | Hardcore Games | Vegan Advocate | PC Reviews

I agree with Victor. I had the same problem and it was due to the time set on the XP machine was out by one year. I could ping xp name, ip address and even remote desktop fine into the xp machine. But shared folder access was only available after I corrected the time on the XP machine.