This is one little annoyance that has been troubling me for some time so i decided to troubleshoot why some of my home PC’s will on occasions seemingly disappear from my network, or at least don’t show in Windows under the local network window. Now before we start, there could be any number of reasons for this, and to mention them all here would be a tall order. So what i will do is mention some of the more common causes and how to resolve them, but with the caveat that your particular issue may be something else entirely.

1. Is it plugged in, turned on and working as you would expect? Well duh..

I know this is obvious, but before you start to tinker make sure the device is actually turned on, connected at both the device and the switch/router with a network cable (or wireless) and operating normally. Look for any obvious problems like a loose network cable, or a server that is powered down or asleep, or showing some sign of fault like a flashing error LED or beeping noise.  Check connectivity by pinging the device or accessing it remotely via a network share or remote desktop.

To ping a device you need to know the IP address or the host name. Open a command prompt (Start Run, “CMD”) and type “ping <IP ADDRESS>” or “ping <HOSTNAME>”. You should see no loss or dropped packets. If you get a timed out error then you know there is something wrong with the device or the network connectivity.

 

2. File Sharing and Default Work group Settings

First of all it’s important to check that all PC’s connected to your network are configured to use CIFS/SMB file sharing (SAMBA explicitly) and are part of the same work-group. Don’t be fooled into thinking that because all your workstations run Windows, they will all belong to the same work-group.  Microsoft has changed their default work-group from MSHOME, used in all releases prior to Windows XP (Home Edition), to WORKGROUP used in all releases after Windows XP (Professional), including Windows 7 & 8. Yes weird as it sounds Microsoft used multiple work-group names for Windows XP dependent on the version purchased. If you have PC’s on your network that are not running Windows it is likely that these will need additional configuration before they can be seen and able to access or share files with Windows PC’s.

To see a list of all the Work-groups on your LAN type “net view /domain” into the CMD prompt. You will see a list of Work-groups present on your LAN. If you have more than one listed you can find out which PC’s belong to each by using the following CMD “net view /domian:WORKGROUP (substituting WORKGROUP with the name of your Work-group).

 

If you determine that some of the PC’s are connected to another work-group you can change them by following one of the guides below, depending on the Operating System you use.

Click here to find out how to change the default windows work-group.

Click here to find out how to set the default work-group in OpenElec/XBMC.

Click here to find out how to install SAMBA and set the default work-group in Ubuntu Linux.

Click here to find out how to set the default work-group in OSX.

3. Determine which machine should be designated as the default Master Browser

In a nutshell, the role of the Master Browser service is to hold and distribute a list of computers sharing resources connected to your local network (or keep track of the computers on your network). This list is what can be seen when you open and browse your “Network”. Specifically there can only be one Master Browser, which is assigned through an election process held between all the computers on your network, and designated based on (amongst other things) the uptime and availability of all devices, the OS level, or if it is a server. Election preference is given to the device which has been available and on-line the longest, re-electing a new Master Browser periodically as required based on the above conditions.

Although not without it’s drawbacks this process generally works well, however occasionally the Master Browser may be assigned to a PC which is not suitable for the role, despite meeting the given criteria. In my case this happens a lot with my HTPC, which spends a lot of time in hibernation, and gets rebooted at irregular times with no particular schedule. Each time this happens the master browser list is destroyed and the election process restarts in order to find a new master browser. This election process is not quick, it can take some time to complete and propagate to all the other PC’s on the network.

The key message here is that the Master Browser ideally should be a PC that is always on, or at least stable (does not get rebooted often) and available more than other machines on the network. This way the master browser list is maintained and more accurately reflects a more complete view of your network, the devices connected to it, and the shares available on each device.

In a corporate or work environment there is generally a dedicated machine assigned this role, usually within a domain and acting as the Primary Domain Controller. This method has far fewer drawbacks associated with it but is not a good fit for the average home. In order to resolve this issue at home, we will adopt a similar principle and help ‘rig the election’ so that the machine which best suits this role is given priority as the Master Browser.

In my case the ideal Master Browser would be my office workstation.

To determine which machine is currently elected as the master browser type “nbtstat -a HOSTNAME” at the command prompt (substituting HOSTNAME with the name of a PC on your LAN). Depending on how many devices you have this may take awhile. The machine that is currently elected as master browser will have a ..__MSBROWSE__ property as shown in the list below.

4. Configure a Windows based PC to be the preferred Master Browser

Open the registry editor (Start > Run, type “regedit”) and navigate to HKEY_LOCAL_MACHINE > SYSTEM > CurrentControlSet > Services > Browser > Parameters.

Right click the “isDomainMaster” string and select Modify. Change the value to “True” and press OK. If the “isDomainMaster” string does not exist you can create it by right clicking and selecting New  “String Value”. Rename “New Value #1” to “isDomainMaster” and proceed as above.

Close the registry editor and restart your machine.

5. Configure a Linux or OSX based PC to be the preferred Master Browser

Navigate to and open /storage/.config/samba.conf. There is usually a sample one in the directory that can be renamed if it doesn’t already exist.

Modify (or add) the following lines below to the [global] section:

domain master = yes  
local master = yes  
preferred master = yes  
os level = 100

Save the file as “samba.conf” and restart the machine.

Remember, only one machine should be designated as the preferred master browser.

6. Configure a Network Storage device as the preferred Master Browser

Open the management console or web management interface, login as admin and navigate to the Control Panel, WIN/MAC/NFS, Windows File Service.

Tick the check box next to “Enable Local Master Browser”, click OK or Save.

Be warned however that enabling this service on a PC or NAS that’s accessible from outside your home network (i.e. The Internet) can be a security risk, as it generally enables the in-built guest account without a password. It will also prevent the machine from entering hibernation.

These steps are based on a Synology NAS, they may differ slightly for other models. Refer to the manual or help if you cannot find it.

7. Finally on a Windows PC make sure that Network Discovery is turned on, and that your network is set to Private (Home or Work, but not Public).

If you are using a 3rd party firewall you will need to open ports for file and print sharing.

Detailed instructions can be found on the Microsoft Windows website.

 

So in summary if you find PC’s to be missing from your home network try the following steps in sequence:

1. Check for connectivity, try to ping the device first, is it switched on and connected to the network
2. Check all devices belong to the same Work-group
3. Verify that the Master Browser is configured properly
4. Make sure Network Discovery and File and Print Sharing is enabled, and that your network is set to Private.