win 10 machine can't access network shares on pdc, intermittent

Question

I manage a small windows domain for my home/home office. It consists of a PDC running Windows Server 2003 SP1 (I know! it's old! etc.) and a hand full of computers with fixed private IP addresses (10.x.x.x):

3 Win 10-64 Pro

1 Win 8.1-64 Pro

2 Win 7 Pro (one 64-bit, one 32-bit)

1 Win XP-32

My intermittent problem for the past year or so is that one of the Win 10 machines occasionally (maybe 3 times/month) suddenly cannot access any network shares on the PDC. This causes a number of automated backup processes to fail. When this happens:

(machine names and IP addresses changed to protect the guilty! :-)

- it can ping the PDC by name, so DNS is not the issue

C:\Users\XXX>ping MyServer


Pinging MyServer [10.x.x.x] with 32 bytes of data:

Reply from 10.x.x.x: bytes=32 time=1ms TTL=128

Reply from 10.x.x.x: bytes=32 time<1ms TTL=128

Reply from 10.x.x.x: bytes=32 time=1ms TTL=128

Reply from 10.x.x.x: bytes=32 time=1ms TTL=128


Ping statistics for 10.x.x.x:

Packets: Sent = 4, Received = 4, Lost = 0 (0% loss),

Approximate round trip times in milli-seconds:

Minimum = 0ms, Maximum = 1ms, Average = 0ms

- this fails, with a fairly long delay before the error message appears (perhaps 2 minutes):

C:\Users\XXX>dir \\MyServer\backupfiles

The semaphore timeout period has expired.

- and yet this works:

C:\Users\XXX>dir \\10.x.x.x\backupfiles

Volume in drive \\10.x.x.x\backupfiles is zzzz

Volume Serial Number is 10C0-79BC


Directory of \\10.x.x.x\backupfiles


05/09/2021 08:28 AM <DIR> .

05/09/2021 08:28 AM <DIR> ..

05/13/2019 09:53 AM 23 BackupCacheRoot.txt

03/21/2019 12:14 PM 23 BackupRoot-ZZZZ.txt

03/21/2019 12:14 PM 23 BackupRoot.txt

05/25/2019 11:53 AM 23 BackupStagingRoot.txt

07/27/2020 10:43 AM 22 BatchFolder.txt

03/24/2019 09:36 AM 24 BatchJobFolder.txt

05/14/2019 08:13 PM 1,510 GetBackupLoc.bat

7 File(s) 1,648 bytes

2 Dir(s) 4,306,067,456 bytes free

- it can connect to network shares on other machines

The only way I can clear this is by rebooting the win 10 machine, after which all is well ... for perhaps a week.

I'd be grateful for any insights anyone may have.

Answer 1

Hello @Blaise ,

I think that your problem may be related to other reported problems in this forum and we may be getting closer to an understanding of the root cause. The problem seems to affect older Network Attached Storage devices and Windows 2003 and earlier. I have included part of another post of mine here, adapted to your scenario.

The authoritative source of information about SMB is the Microsoft specification "[MS-SMB2]: Server Message Block (SMB) Protocol Versions 2 and 3".

Section "3.2.4.2.2 Negotiating the Protocol" of this document says:

When a new connection is established, the client MUST negotiate capabilities with the server. The
client MAY<111> use either of two possible methods for negotiation.

The first is a multi-protocol negotiation that involves sending an SMB message to negotiate the use of
SMB2. If the server does not implement the SMB 2 Protocol, this method allows the negotiation to fall
back to older SMB dialects, as specified in [MS-SMB].

The second method is to send an SMB2-Only negotiate message. This method will result in successful
negotiation only for servers that implement the SMB 2 Protocol.

The footnote <111> says:

The Windows-based client will initiate a multi-protocol negotiation unless it
has previously negotiated with this server and the negotiated server's DialectRevision is equal to
0x0202, 0x0210, 0x0300, 0x0302, or 0x0311. In the latter case, it will initiate an SMB2-Only
negotiate.

What might be happening is that your clients are attempting to reconnect to the Windows 2003 PDC (after an interruption in the TCP/IP connection) using an SMB2-Only negotiate message. Windows 2003 seems to just silently ignore this negotiate message, perhaps expecting the first SMB message on a new connection to always be a multi-protocol negotiation.

If you issue a "net use" command on a client that can't connect, you might see something like:

New connections will not be remembered.  
  
  
Status       Local     Remote                    Network  
  
-------------------------------------------------------------------------------  
Disconnected           \\ray\c$                  Microsoft Windows Network  
The command completed successfully.  

If you do see that, try issuing the command "net use \ray\c$ /d" for all of the connections to that server (e.g. "ray"). The reason for doing this is that the client remembers that it negotiated an SMB2/SMB3 connection with the server and skips the multi-protocol negotiation; removing all connections to the server also causes this "remembered" information about protocol capabilities of the server to be deleted.

After this, it should be possible to re-establish connections to the Windows 2003 system.

Please let us know what experiences you have with this approach - it would help to build a body of evidence for the problem.

Gary

Answer 2

UPDATE

After following suggestions @DSPatric, the win 10 machine was fine for a couple of weeks. The issue then started happening again. It seems so random - sometimes happening once every couple of days, other times happening a few times in one day. So, although the suggestions from @Dave Patrick were all solid, they don't seem to address the cause of my issue.

Looking at the reply from @Gary Nebbett I tried the following on the win 10 machine when it was experiencing the problem:

C:\Users\Pat>net use  
New connections will be remembered.  
  
  
Status       Local     Remote                    Network  
  
-------------------------------------------------------------------------------  
Reconnecting P:        \\BSSMSV02\Pat            Microsoft Windows Network  
The command completed successfully.  
  
  
C:\Users\Pat>dir p:\  
The semaphore timeout period has expired.  
  
C:\Users\Pat>  

On this machine P: is a persistent mapped drive to a share on the Win 2003 PDC. I totally forgot this was here, Hmm, I rebooted the machine and got this:

C:\Users\Pat>net use  
New connections will be remembered.  
  
  
Status       Local     Remote                    Network  
  
-------------------------------------------------------------------------------  
OK           P:        \\BSSMSV02\Pat            Microsoft Windows Network  
The command completed successfully.  
  
  
C:\Users\Pat>  

So either the problem also causes the P: drive disconnect, or maybe the problem is caused by the P: drive mapping getting disconnected. I deleted the mapped drive, and we'll see if the problem continues to occur.

Gary, you may have hit the nail on the head. In retrospect, I should have tried what you suggested (net use \ray\c$ /d). But I figured that perhaps the scenario you described is occurring because the connection to the mapped drive dropped.

I'll post an update when I have more information.

Thanks.

Answer 3

Please put up a new set of files to look at.