question

ChristophSchneider-2258 avatar image
0 Votes"
ChristophSchneider-2258 asked GaryNebbett commented

Windows Explorer not showing all connected network drive

Hello,

I have the problem that at two of our costumers there is the problem that sometimes network drives do not show up in the Windows Explorer.

Environment:

One costumer is using Windows 10 Clients the other is using a Windows 2016 Terminal Server. Only thing similar is that they both use a Windows Server 2016 as Data Server. We map the dives via script at one and via GPO at the other.

More about the problem:

The systems are up to date.

When I open a CMD at the client having the problem and enter "net use" I see all drives connected. I can change to the drive using cd and can then list content but only in the cmd. The explorer is not showing the drive. When I enter the dive letter for example "X:" manual into the explorer the error "Cannot access X:" shows up.

The error can be resolved by restarting the explorer.exe process.

It seems that not all users are having this issue. I would say 1 out of 10 is affected. The issue occurs not direct at logon. It only appears after some time. Somehow it does also not affect all Drives

What I tried:

I tried to set the reg key:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System
DWORD
EnableLinkedConnections
1
as described here in Solution 1 at this link mapped-network-drive-not-showing.html.

Does anyone have a similar problem or any tips on how to solve this?

Kind regards
Christoph Schneider



windows-10-generalwindows-server-2016
5 |1600 characters needed characters left characters exceeded

Up to 10 attachments (including images) can be used with a maximum of 3.0 MiB each and 30.0 MiB total.

GaryNebbett avatar image
0 Votes"
GaryNebbett answered GaryNebbett published

Hello @ChristophSchneider-2258,

I guess that you are from a German speaking region and that the error message "Cannot access X:" is a translation; while that translation might capture the essential nature of the problem, it would be useful to know the exact text (in German) so that one can accurately map the error text to an error code. Was the error message in Windows File Explorer perhaps "Die Datei X:\ wurde nicht gefunden"?

The "linking" (or not) of connections between sessions does sound as though it might be playing a role, but you have already identified the key registry setting (EnableLinkedConnections).

I would suggest exploring the Windows Object Namespace (using a tool of your choice (https://docs.microsoft.com/en-us/sysinternals/downloads/winobj would be one option)), especially the \Sessions\<n>\DosDevices subtrees, looking for links to \Device\LanmanRedirector\;X:[...] and perhaps correlating this information with the output of klist sessions.

For example:

Directory of: \Sessions\0\DosDevices

00000000-000003e4 Directory
00000000-000003e5 Directory
00000000-00013174 Directory
00000000-00019f5e Directory
00000000-0001adf6 Directory
00000000-00161805 Directory
00000000-00161902 Directory

Directory of: \Sessions\0\DosDevices\00000000-000003e4

Global SymbolicLink -> \Global??
NDISTAPI SymbolicLink -> \Device\NdisTapi

Directory of: \Sessions\0\DosDevices\00000000-000003e5

Global SymbolicLink -> \Global??

Directory of: \Sessions\0\DosDevices\00000000-00013174

Global SymbolicLink -> \Global??

Directory of: \Sessions\0\DosDevices\00000000-00019f5e

Global SymbolicLink -> \Global??

Directory of: \Sessions\0\DosDevices\00000000-0001adf6

Global SymbolicLink -> \Global??

Directory of: \Sessions\0\DosDevices\00000000-00161805

Global SymbolicLink -> \Global??
X: SymbolicLink -> \Device\LanmanRedirector\;X:0000000000161805\ray\c$

Directory of: \Sessions\0\DosDevices\00000000-00161902

Global SymbolicLink -> \Global??

klist sessions

Current LogonId is 0:0x161805
[0] Session 1 0:0x161902 GARY\Gary NTLM:Interactive
[1] Session 1 0:0x161805 GARY\Gary NTLM:Interactive
[2] Session 1 0:0x1adf6 Window Manager\DWM-1 Negotiate:Interactive
[3] Session 1 0:0x1add9 Window Manager\DWM-1 Negotiate:Interactive
[4] Session 1 0:0x19f5e Font Driver Host\UMFD-1 Negotiate:Interactive
[5] Session 0 0:0x3e4 WORKGROUP\GARY$ Negotiate:Service
[6] Session 0 0:0x3e5 NT AUTHORITY\LOCAL SERVICE Negotiate:Service
[7] Session 0 0:0x13174 Font Driver Host\UMFD-0 Negotiate:Interactive
[8] Session 0 0:0x12d74 \ NTLM:(0)
[9] Session 0 0:0x3e7 WORKGROUP\GARY$ NTLM:(0)

Gary

5 |1600 characters needed characters left characters exceeded

Up to 10 attachments (including images) can be used with a maximum of 3.0 MiB each and 30.0 MiB total.

ChristophSchneider-2258 avatar image
0 Votes"
ChristophSchneider-2258 answered ChristophSchneider-2258 edited

Hello @GaryNebbett ,

thank you for your answer. The exact German error code is "Die Datei "L:\" wurde nicht gefunden. Überprüfen Sie die Schreibweise, und wiederholen Sie den Vorgang"

The command klist sessions provided the following output.

Aktuelle Anmelde-ID ist 0:0x1f84261
[11] Sitzung 10 0:0x1f84261 Domain\USER Kerberos:RemoteInteractive

\Sessions\0\DosDevices\00000000-01f84261

Here the screenshot from the WinObj Tool:

123788-2021-08-17-10-11-25.png




In this case the Drives F:, H:, I:, O:, Q:, and S: were showing correct. P:, R:, J:, K:, L: and M: were not showing in the explorer.

Kind regards
Christoph Schneider


5 |1600 characters needed characters left characters exceeded

Up to 10 attachments (including images) can be used with a maximum of 3.0 MiB each and 30.0 MiB total.

GaryNebbett avatar image
0 Votes"
GaryNebbett answered

Hello Christoph,

Just to be sure, did you inspect all of the other folders under \Sessions\0\DosDevices? With EnableLinkedConnections set to one, the drive links could appear in more than one folder:


Directory of: \Sessions\0\DosDevices\00000000-000307d7

Global SymbolicLink -> \Global??
X: SymbolicLink -> \Device\LanmanRedirector\;X:00000000000307d7\ray\c$

Directory of: \Sessions\0\DosDevices\00000000-0003096c

Global SymbolicLink -> \Global??
X: SymbolicLink -> \Device\LanmanRedirector\;X:00000000000307d7\ray\c$


Current LogonId is 0:0x307d7
[0] Session 1 0:0x3096c GARY\Gary NTLM:Interactive
[1] Session 1 0:0x307d7 GARY\Gary NTLM:Interactive

In particular, is there any (WinObj) folder where links for F:, H:, I:, O:, Q:, and S: are present, but the other drive letters are missing?

Gary

5 |1600 characters needed characters left characters exceeded

Up to 10 attachments (including images) can be used with a maximum of 3.0 MiB each and 30.0 MiB total.

ChristophSchneider-2258 avatar image
0 Votes"
ChristophSchneider-2258 answered

Hello Gary,

no I did not check the other folders. I will do so when the error occurs the next time.

Kind regards
Christoph Schneider

5 |1600 characters needed characters left characters exceeded

Up to 10 attachments (including images) can be used with a maximum of 3.0 MiB each and 30.0 MiB total.

ChristophSchneider-2258 avatar image
0 Votes"
ChristophSchneider-2258 answered GaryNebbett commented

Hello Gary,

it has been a while. I am sorry for the long delay but its seems that the error does not happen realy often anymore but it is still there.
I collected new information from a PC. In this case only the letter M: was visable in the explorer. There is no other folder with the dives in it. The Session of the user was 0:0xcf8b8. There was no other Session with the users name in it.

C:\WINDOWS\system32>klist sessions

Aktuelle Anmelde-ID ist 0:0x13625f2
[0] Sitzung 1 0:0x13625f2 DOMIAN\ADMIN Kerberos:CachedInteractive
[1] Sitzung 1 0:0x13076e6 DOMIAN\ADMIN Kerberos:CachedInteractive
[2] Sitzung 1 0:0x12cc89e DOMIAN\ADMIN Kerberos:CachedInteractive
[3] Sitzung 1 0:0xcf8b8 DOMIAN\USERNAME Kerberos:Interactive
[4] Sitzung 0 0:0x3e3 NT-AUTORITÄT\IUSR Negotiate:Service
[5] Sitzung 0 0:0x3e5 NT-AUTORITÄT\Lokaler Dienst Negotiate:Service
[6] Sitzung 1 0:0x188ba Window Manager\DWM-1 Negotiate:Interactive
[7] Sitzung 1 0:0x18870 Window Manager\DWM-1 Negotiate:Interactive
[8] Sitzung 0 0:0x3e4 DOMIAN\PCNAME Negotiate:Service
[9] Sitzung 1 0:0x1202a Font Driver Host\UMFD-1 Negotiate:Interactive
[10] Sitzung 0 0:0x11fe1 Font Driver Host\UMFD-0 Negotiate:Interactive
[11] Sitzung 0 0:0x11af4 \ NTLM:(0)
[12] Sitzung 0 0:0x3e7 DOMIAN\PCNAME Negotiate:(0)

\Sessions\0\DosDevices

\Sessions\0\DosDevices\00000000-0001202a
Global SymbolicLink -> \Global??

\Sessions\0\DosDevices\00000000-000003e4
Global SymbolicLink -> \Global??
NDISTAPI SymbolicLink -> \Device\NdisTapi

\Sessions\0\DosDevices\00000000-000003e5
Global SymbolicLink -> \Global??

\Sessions\0\DosDevices\00000000-00011fe1
Global SymbolicLink -> \Global??

\Sessions\0\DosDevices\00000000-000cf8b8
Global SymbolicLink -> \Global??
I: SymbolicLink -> \Device\LanmanRedirector\;I:00000000000cf8b8\DATASERVER\SHARENAME
J: SymbolicLink -> \Device\LanmanRedirector\;J:00000000000cf8b8\DATASERVER\SHARENAME
K: SymbolicLink -> \Device\LanmanRedirector\;K:00000000000cf8b8\APPSERVER\SHARENAME
L: SymbolicLink -> \Device\LanmanRedirector\;L:00000000000cf8b8\DATASERVER\SHARENAME
M: SymbolicLink -> \Device\LanmanRedirector\;M:00000000000cf8b8\DATASERVER\USERSHARE
N: SymbolicLink -> \Device\LanmanRedirector\;N:00000000000cf8b8\DATASERVER\SHARENAME
O: SymbolicLink -> \Device\LanmanRedirector\;O:00000000000cf8b8\DATASERVER\SHARENAME
Q: SymbolicLink -> \Device\LanmanRedirector\;Q:00000000000cf8b8\DATASERVER\SHARENAME
R: SymbolicLink -> \Device\LanmanRedirector\;R:00000000000cf8b8\DATASERVER\SHARENAME
S: SymbolicLink -> \Device\LanmanRedirector\;S:00000000000cf8b8\DATASERVER\SHARENAME
T: SymbolicLink -> \Device\LanmanRedirector\;T:00000000000cf8b8\DATASERVER\SHARENAME
U: SymbolicLink -> \Device\LanmanRedirector\;U:00000000000cf8b8\DATASERVER\SHARENAME
V: SymbolicLink -> \Device\LanmanRedirector\;V:00000000000cf8b8\DATASERVER\SHARENAME
W: SymbolicLink -> \Device\LanmanRedirector\;W:00000000000cf8b8\DATASERVER\SHARENAME
X: SymbolicLink -> \Device\LanmanRedirector\;X:00000000000cf8b8\DATASERVER\SHARENAME

\Sessions\0\DosDevices\00000000-000188ba
Global SymbolicLink -> \Global??

\Sessions\0\DosDevices\00000000-012cc89e
Global SymbolicLink -> \Global??

Kind regards
Christoph Schneider

· 1
5 |1600 characters needed characters left characters exceeded

Up to 10 attachments (including images) can be used with a maximum of 3.0 MiB each and 30.0 MiB total.

Hello Christoph,

That latest data provides no further useful hints for me about possible causes of the problem.

The long interval between occurrences of the problem and the need to protect the privacy of your data eliminates all other ideas that I have for troubleshooting the problem.

If the problem occurred on my equipment with that frequency (monthly or longer), what I would probably do is to create a Live Kernel Dump of the system when the problem was visible (to give me more time to analyse the state of the system) - this is not something that I suggest that you do.

I would also see if it was possible to use Event Tracing for Windows to trace potentially relevant events leading up to the problem in a circular buffer and use a custom trigger to stop the trace when the problem occurred; this requires programming and is also something that I would not suggest for you.

Gary

0 Votes 0 ·