Fix 0X0000085B: NERR_BrowserNotStarted Error

You hit the 0X0000085B error — that NERR_BrowserNotStarted message. It's frustrating when network shares just vanish.

The core problem is simple: the Computer Browser service on Windows isn't running. This service maintains the list of network machines you see in File Explorer. Without it, you get this error when something tries to enumerate the network (like net view or an old app).

The Fix

Restart the Server service — open an admin Command Prompt (cmd as Administrator) and run:

net stop server && net start server

This stops and starts the Server service, which the Computer Browser depends on. The Server service handles file/print sharing. If it's stuck, the browser service won't start.

Check that the Computer Browser service is set to start automatically — run:

sc query browser

Look for STATE : 4 RUNNING. If you see STOPPED, the service is off. The reason it's often disabled: Microsoft turned off SMB1 by default after the WannaCry attacks, and the Computer Browser service relies on SMB1.

Enable the Computer Browser service — if it's stopped, run:

sc config browser start= demand
net start browser

start= demand sets it to manual start. But you need the SMB1 feature enabled for this to work long-term. Run:

dism /online /enable-feature /featurename:SMB1Protocol

This installs SMB1 (including the browser service). After this, restart. Now browser will start when something asks for network browsing.

Why This Works

What's actually happening here is the Server service is the parent. The Computer Browser service registers with the Server service to announce itself to other machines on the subnet. If the Server service isn't running, or if SMB1 is fully removed (not just disabled), the browser service can't start. The error 0X0000085B comes from the network provider layer when it calls NetServerEnum — the API that lists servers — and the browser service isn't responding. The fix restarts the chain: Server service -> SMB1 support -> browser service.

Less Common Variations

1. The SMB1 feature is disabled but you don't want to enable it

If you're on a domain, you can rely on the Domain Master Browser — but in small workgroups, you need SMB1 on at least one machine. For Windows 10/11, you can try enabling the browser service via registry instead:

reg add "HKLM\SYSTEM\CurrentControlSet\Services\Browser" /v Start /t REG_DWORD /d 3 /f

Set Start=3 (manual), then reboot. But without SMB1, the Browser service binary won't be present. If the service doesn't exist at all, you have to enable SMB1.

2. The error appears from a legacy app, not from net view

Some old custom software or network management tools call NetServerEnum directly. In that case, the fix is the same — but you can also bypass the browser service entirely by using direct IP connections in the app config.

3. Windows Server 2019/2022 with the browser service removed

Starting from Windows Server 2019, the Computer Browser service is completely removed (not just disabled). The registry key and sc config won't help. In that case, the only fix is to use an alternative method (DNS, WINS, or direct IPs) for network discovery. Or install a third-party browser service — but that's rare.

Prevention

Don't disable SMB1 if you have legacy network apps — use Group Policy to set Smb1 to enabled on machines that need to browse.
Monitor the Server service — set a scheduled task to restart it daily if you see intermittent errors.
Use WINS or DNS for name resolution — if the browser service is off, these fallback methods can still let you access shares by name.
Keep a note of your SMB1 state — run sc query browser after any major Windows update. Updates sometimes reset the browser service start type.

One last thing: if you're running Windows 10 20H2 or later, Microsoft made SMB1 an optional feature you have to install via Windows Features. If you don't see "SMB 1.0/CIFS File Sharing Support" in the list, you can't fix this without enabling it. Know that SMB1 is old and insecure — only use it in isolated networks.