Windows networking suddenly not working across the LAN

I have a small LAN containing three PCs (two on Win7 Ultimate x64 and one on XP Pro), a Samsung network laser, and a Drobo box (with DroboShare).

At some point in the recent past (and I'm not sure quite when), it appears that sharing and device discovery across the LAN have stopped working.

I'm thinking that it must be either a Windows update or an AVG update that has changed something - other protocols seem to work OK (POP, SMTP, and some proprietary ones are all working).

It's not a general IP connectivity issue: all the machines can access the internet etc, and one another over different protocols (e.g. VNC and email protocols), it's just Windows networking that's failed.

All machines use DHCP but with IP addresses that are consistent due to MAC binding in the router.

All PCs are in a workgroup (one machine is XP, so we don't use Homegroup).

Any pointers?

Marc Wilson

Posted 2014-04-30T18:14:55.497

Reputation: 146

You can't see hosts in workgroup browser? – Nafscript – 2015-06-10T04:50:13.777

Answers

I would verify windows sharing is still enabled.

On Windows 7 under Network and Sharing Center in the left pane, click Change advanced sharing settings and expand your current network profile.

l0sts0ck

Posted 2014-04-30T18:14:55.497

Reputation: 11

When I click on the "Network" in the left pane, it shows the machine I'm working on (which is called MEMPHIS). If I try to expand that, it says \MEMPHIS is not accessible. You may not have permission to use this network resource. Contact the administrator of this server to find out if you have access permissions.

The Server service is not started. – Marc Wilson – 2014-04-30T18:33:10.373

Confirm you have windows sharing enabled on both windows 7 machines. What network location do you have selected for your network? (Home, Work, Public?) – None – 2014-04-30T18:37:34.710

Work.

I've found another issue: there appears to be a missing service in my current machine. When I get open the Services snap-in, the "Server" service is indeed not running. In fact, it's not even listed! It seems to have disappeared from the list of services. – Marc Wilson – 2014-04-30T18:44:03.070

That'll do it. Click Start, Run. Type ncpa.cpl. Right-click on the LAN connection, and choose Properties. Click Install Select Service, and click Add. Select File and Printer Sharing for Microsoft Networks and Click OK. That should reinstall that server service. – None – 2014-04-30T18:47:20.463

I can get as far as "Add" - it then comes up with an empty box, with the only option being to select "Have Disk". – Marc Wilson – 2014-04-30T19:54:56.777

Hmmm. I've found srvsvc.dll. It has the right size and date, but the description is wrong: it says "NVIDIA shim installation dll" and it also says "Original filename: nvinit.dll"

Sounds like something is badly corrupted, even if it's just the file metadata. – Marc Wilson – 2014-04-30T20:11:38.627

Curiouser and curiouser. I've deleted that file, using the very useful delnext.exe

Then I've copied the file from a working instance of Windows 7. Attempted again to start the service- fails again, same error. Checking the metadata, it again thinks it's an NVIDIA file.

I think I'm staring down the barrel of a complete re-install; something is badly goosed. – Marc Wilson – 2014-05-20T13:49:45.933

That's probably your best bet. If you spend more hours trying to fix something and restaging is an option, that's probably your best route at this point. You can spend 12 hours trying to figure it out or 3 hours restaging the system. – l0sts0ck – 2014-05-21T14:28:04.340

It'll take quite a bit longer than 3 hours- I've got quite a bit of software installed on this machine.

Nevertheless, the principle is sound. – Marc Wilson – 2014-05-21T16:40:59.677

I Just had EXACTLY the same problem happen SUDDENLY to my LAN Network.. - I have Three-Four PCs Interconnected thru a Router (Win7 LT, Win8.1 DT, Win10TP DT, & on occasion, an old WinXP DT) - I use a Workgroup, not Windows HomeGroup - I CONTINUED to have Internet Access throughout my problem with my Local LAN - The thing that appeared VERY Strange was that when I opened my Network it showed ONLY the Router - It wouldn't even show the PC I was on as being part of the Local Network!

SOLUTION: It turned out that, for some reason I still do not know, AVG Firewall TURNED OFF FILE & PRINTER SHARING - When I Re-Enabled File & Printer Sharing thru AVG Firewall, All was Again Well :) - BJ51

BJ51

Posted 2014-04-30T18:14:55.497

Reputation: 1