Note
Access to this page requires authorization. You can try signing in or changing directories.
Access to this page requires authorization. You can try changing directories.
Question
Friday, June 30, 2017 8:58 AM | 2 votes
I have the problem, that port 445 (SMB) is closed after restaring Windows. Port 139 (NetBios) is closed all the time, hence my computer cannot be reached from other computers in the network.
I need to deactive and then activate "file and printer sharing for microsoft networks" on the network adapter to open port 445 again to make my computer accessible temporarily.
Port 139 doesn't open at all, even it is set in the WINS settings.
It's the same problem for all network adaptors (Intel I219-LM, Realtek USB GbE via Thunderbolt, Intel Wireless-AC 8265).
What I tried without success:
- Deactivate firewall, but it can't be a firewall issue, because a portscan on localhost and my IP are showing both the same result for port 445 and 139.
- Change settings back and forth in advanced sharing settings.
- Deactivate Computerbrowser service
- "Network Reset" (from Network and Internet)
- "netsh int ip reset" and "netsh winsock reset"
I'm not sure since when this happend, either with creators update or after installing Cisco VPN, which I know meanwhile has some compatibilty issues with Win10.
2 more interesting details, which might be the same problem.
1. I cannot access to my VMWare Virtual machine on the same computer in bridged mode, must be NAT
2. A VPN connection (Shrew Soft client) to my home Router (AVM FritzBox) is connecting successful but blocking any network traffic. From other devices it runs well.
Maybe someone has an idea how to fix these problems. I have no idea anymore.
Patrick
All replies (11)
Friday, June 30, 2017 9:09 AM
Hi Patrick,
Please check:
Control Panel > Programs and Features
click on [Turn Windows features on or off] (left side of a window)
Check if [SMB 1.0/CIFS File Sharing Support] is checked.
If unchecked, check it and reboot Windows.
[Note] This screenshot is in Win.10 Insider Preview. You will see only [SMB 1.0/CIFS File Sharing Support].
Ashidacchi
Friday, June 30, 2017 9:43 AM
It was checked. But anyway I unchecked, restarted, checked and restarted again, but no change unfortunately.
Any more ideas?
Patrick
Friday, June 30, 2017 9:59 AM
If your PC belongs to your company, I guess, IT dept. must forbid using SMB 1.x. according to security policy.
If so, consult your IT dept.
(As you know, SMB 1.x is a security hole to ransomeware such as WannaCry, Petya.)
If not, please scan your whole computer with antivirus software.
Ashidacchi
Friday, June 30, 2017 10:13 AM
Please refer to this article about SMB:
Disable SMB v1 in Managed Environments with Group Policy
Ashidacchi
Friday, June 30, 2017 10:48 AM
Thanks for your answers.
The security issue is fixed by Microsoft meanwhile and it was patched during the WannaCry attacks, of course virus protected all the time, behind company firewalls and so on, but that's not point of discussion here.
It's a software developer machine in a company domain, but used at customer side and public places as well. I need some more network functions when I'm doing software tests outside the company.
Fact is, that I'm not reachable from other computers inside the company network or other closed networks. It's a pain always to disable/enable "file and printer sharing for microsoft networks" to be accessible. And as far as I know that can't be done by a script, or am I wrong?
What can be the reason that port 445 is closed after restart? Why can't I open port 139, which I sometimes need for clients not running on windows to access to my computer?
Patrick
Friday, June 30, 2017 10:51 AM
Disable SMB v1 in Managed Environments with Group Policy
I want to enable permanently together with NetBios over TCP/IP.
Monday, July 3, 2017 1:39 AM
Hi Patrick,
Please try to use registry method to test result, meanwhile, note your DC group policy settings.
How to enable and disable SMBv1, SMBv2, and SMBv3 in Windows and Windows Server
Regards
Please remember to mark the replies as answers if they help.
If you have feedback for TechNet Subscriber Support, contact [email protected].
Friday, August 4, 2017 2:58 PM | 1 vote
Sorry for answering late, but there was a business trip in between and I reset my computer to an earlier state from backup to hope it resolves the problem, but it didn't.
I looked deeper meanwhile and found the following:
I have 2 ethernet adapters on my Dell 3520 Notebook. First one is the built-in Intel I219-LM, second the Realtek USB GbE connected via TB16 Thunderbolt dock from Dell.
This problem with port 445 and 139 only happens on the Realtek adapter, whereas on the Intel adapter both ports are open when I scan these ports with nmap-zenmap.
The scan on localhost shows port 445 open, port 139 closed.
The scan on Realtek shows port 445 closed, port 139 closed.
The scan on Intel shows port 445 open, port 139 open.
We have a NAS system running, which probably still uses Netbios (139). This is accessible by its name when connected with Intel, with Realtek I have to type in the IP.
With Intel connected, other computers can see me in the network, with Realtek they can't. The firewall of course shows both, port 139 and 445, open any time independent from the network card.
The connection with Realtek is established before log on to my user, all group policies are loaded correctly.
So it seems to be a network adapter related issue, maybe driver? (I checked installed the newest of course)
Maybe this information is helpful.
Patrick
Monday, August 7, 2017 8:29 AM
I tested another Realtek USB GbE directly on an USB port of my Dell Notebook (not via Thunderbolt dock), the situation is the same. The USB adapter on my colleagues computer works normal.
ipconfig/all shows Netbios over TCP/IP deactivated, when I connect the network cable to this adapter and I'm not able to activate it. On the Intel adapter it shows activated, simply by unplug from Realtek and plug in to Intel.
Nevetheless I have the assumption, that it happened as we changed our domain controller to windows server 2016 and switched off our WINS Server. But why does it give problems on my computer only.
By the way, the WLAN adapter runs normal with port 139 and 445 activated.
Patrick
Tuesday, March 12, 2019 2:37 AM
Hi, have you found a solution to this? I'm all of a sudden experiencing the same issue, both port 139 and 445 are not listening. They're not even listed when I run "netstat -a -b" unlike my other machines. Other Windows 10 machines don't have this issue. I have SMB enabled, Network Sharing enabled and NetBIOS forced On under the adapter settings. I have the Intel 1219-V card.
Monday, March 18, 2019 12:21 AM
Hi guys, just letting you that I managed to fix this by reinstalling Windows... what a buggy piece of software Windows 10 is. Basically I changed nothing on my network. Just reinstalled Windows.