Windows network error codes, explained and fixed

1. The network profile is set to Public

On a Public network Windows deliberately hides your PC and refuses incoming connections, because it assumes you are in a cafe. Every home network should be Private. This single setting causes more "I cannot see the other computer" reports than everything else combined, and Windows sometimes switches it back on its own after a router change or a driver update.

Check it: Settings, Network and internet, Wi-Fi or Ethernet, then the network name, then Network profile type. Or from PowerShell:

Get-NetConnectionProfile

2. The firewall is blocking the app or the ports

Windows Defender Firewall, or a third party suite such as ESET, Norton, Bitdefender, Kaspersky, Avast or McAfee, blocks the inbound connection. Third party suites are the harder case: they often install their own firewall that replaces the Windows one, so a rule you added in Windows settings is not the rule that is being enforced.

A detail that costs people hours: firewall rules are usually tied to the exact path of the program. Update or reinstall an app into a new folder and the old allow rule no longer covers it, with no warning.

3. The discovery services are stopped

Three Windows services do the work of finding other computers. If any is stopped, the Network folder goes empty even though everything else is fine.

• fdPHost, Function Discovery Provider Host
• FDResPub, Function Discovery Resource Publication
• SSDPSRV, SSDP Discovery

Some "speed up Windows" tools disable exactly these, which is why a PC can lose discovery on a day nobody touched the network.

4. Guest access and SMB policy

Modern Windows refuses to log in to a share as a guest, and no longer speaks the old SMB1 protocol. This is a security improvement and it is not going to be reverted, but it silently breaks older NAS boxes, older routers with USB disks, and PCs set up years ago.

5. Saved credentials that are no longer correct

Windows remembers the user name and password you used for another PC in Credential Manager, and keeps using it after the password changes. It then fails with a login error and never asks you again, which is why re-typing the password in the prompt does not help: you never see a prompt.

0x80070035 The network path was not found

What it really means. Your PC resolved the name and tried to open a file sharing session, and got nothing back. It is a connectivity or protocol failure, not a permissions failure. If it were permissions you would get a password prompt or access denied instead.

In order of how often it is the cause:

1. The other PC has its network profile on Public. Fix that first, on the PC you are trying to reach, not on yours.
2. File and printer sharing is off on the target. Settings, Network and internet, Advanced network settings, Advanced sharing settings.
3. The firewall on the target is blocking inbound SMB on port 445.
4. The name does not resolve. Try the IP address instead: \\192.168.1.42. If the IP works and the name does not, it is a name resolution problem, not a sharing problem.
5. The target only speaks SMB1, which modern Windows no longer has installed. Common with NAS units and routers with a USB disk, more than seven or eight years old.

Test whether the file sharing port is even reachable, from the PC that is failing:

Test-NetConnection -ComputerName 192.168.1.42 -Port 445

TcpTestSucceeded : True means the network and firewall are fine and the problem is above that layer. False means it is the firewall, the profile, or the machine is off.

0x80004005 Unspecified error

What it really means. Genuinely nothing. 0x80004005 is the generic COM failure code, E_FAIL, and Windows uses it when the layer that failed did not supply a reason. So this code by itself identifies no cause.

In home file sharing, it is nearly always one of two things:

1. Guest access is blocked by policy, and the share you are opening allows only guests. See the guest access section, which has the exact wording and the correct fix.
2. SMB1 is involved. Either the target only offers it, or an old SMB1 client entry is still in place on yours.

It is also worth ruling out a stale saved credential, because a bad credential sometimes surfaces here rather than as a login error.

0x8007052E The user name or password is incorrect

What it really means. Exactly what it says, and the frustrating part is that the credentials it is using are usually not the ones you just typed. Windows stores them and reuses them silently.

The fix that actually works:

1. Open Credential Manager (search for it in the Start menu), then Windows Credentials.
2. Remove every entry that names the PC you are trying to reach, including entries that start with Domain:target=.
3. Reconnect. You should now be asked for a user name and password.

Or from a command prompt, to see and clear what is cached:

cmdkey /list
net use * /delete

One more trap: if the other PC signs in with a Microsoft account, the user name is usually the full email address, and the password is the Microsoft account password, not the PIN. A PIN never works for network sharing.

0x80070043 The network name cannot be found

What it really means. You reached the other computer, and it told you that the share you asked for does not exist. Note the difference from 0x80070035: there, the computer never answered. Here it answered and said no.

So the machine, the network, the firewall and the profile are all fine. Check the share name itself:

1. The folder was un-shared, renamed, or the drive letter changed.
2. You are using the folder name rather than the share name. They are often different.
3. The share is hidden. Names ending in $ exist but are not listed.

List what the other PC is really offering:

net view \\PC-NAME

0x800704B3 The network provider is not currently available

What it really means. The part of Windows that handles network drives, the Workstation service and its network providers, is not running or is misconfigured on your PC. This one is local, which is why it is worth separating from the codes above.

1. Make sure the Workstation service is running: services.msc, find Workstation, set it to Automatic and start it.
2. Check that Client for Microsoft Networks is ticked in the adapter properties.
3. Reset the network stack, then restart:

netsh winsock reset
netsh int ip reset

0x80070079 The semaphore timeout period has expired

What it really means. This one is different from all the others on this page: it is a physical layer complaint. The connection was established and then stalled long enough for Windows to give up. Settings are rarely the cause.

Look at hardware and drivers, in this order:

1. A failing cable or port. Swap the Ethernet cable first. It is the single most common cause and the cheapest to rule out.
2. Network adapter power saving. Device Manager, your adapter, Properties, Power Management, untick Allow the computer to turn off this device to save power.
3. Large Send Offload. In the same Properties, Advanced tab, disable Large Send Offload for both IPv4 and IPv6. Old and mismatched offload implementations stall large transfers specifically.
4. Wi-Fi at the edge of range, or a mesh node handing over mid transfer.

A useful signal: if small files copy and large ones fail part way, it is almost certainly this class of problem rather than a permissions or discovery one.

0x8007003B An unexpected network error occurred

What it really means. The SMB session dropped mid conversation. Like 0x80070079 it points at something interrupting an established connection rather than at a setting that blocked it.

1. Antivirus scanning network traffic. Suites with a "network shield" or "web protection" module sometimes break long SMB transfers. Temporarily disabling that module is a fair test; if it fixes it, add an exclusion rather than leaving protection off.
2. SMB signing or encryption mismatch between a modern Windows client and an older device. See what Windows 11 changed.
3. The same cable and offload checks as above.

0x80070040 The specified network name is no longer available

What it really means. You had a working session and it was torn down from the other end. The connection existed, which rules out most of the discovery and firewall causes.

1. The other PC went to sleep, or its network adapter did. This is extremely common on desktops with fast startup and default power settings.
2. The other PC hit its connection limit. Windows client editions allow only 20 simultaneous incoming sharing connections.
3. Wi-Fi roamed to another access point mid session.

0x80070032 The request is not supported

What it really means. The two machines could not agree on a protocol they both speak. In practice this is the SMB1 conversation: your Windows no longer offers it, and the device on the other side offers nothing else.

The right fix is on the other device, not on your PC: update its firmware, or enable SMB2 or SMB3 in its settings. Almost every NAS made in the last decade supports SMB2 and simply ships with it off.

This wording confuses people because most of them have no organization. It appears on ordinary home PCs.

What happened. Windows used to let you open a share with no credentials at all, as "guest". Since Windows 10 version 1709 that is disabled by default, because an attacker on your network could offer a malicious share and your PC would connect to it without asking you anything.

The correct fix is on the machine hosting the share: give it a real user account with a password, and connect with that user name and password. That takes two minutes and leaves you safer than you were.

System error 53: The network path was not found

The command line twin of 0x80070035, and the same causes apply. The host could not be reached on the file sharing port. Start with the network profile and the firewall on the target.

System error 1219: Multiple connections to a server by the same user

Windows allows exactly one identity per remote machine at a time. You already have a session open to that PC, often a mapped drive you forgot about, using different credentials.

net use
net use * /delete

Then connect again. This is one of the few Windows network errors with a genuinely complete and reliable fix.

System error 6118: The list of servers for this workgroup is not currently available

Browsing, the mechanism that produces the list of computers, is not working. Nearly always the FDResPub and fdPHost services being stopped, or the network profile being Public.

Worth knowing: the old Computer Browser service that this message dates from is gone from modern Windows. Discovery now runs on WS-Discovery, which is what those two services provide. That is why enabling the Computer Browser service, which many old guides recommend, does nothing on Windows 10 or 11.

System error 5: Access is denied

You reached the machine and it refused you. This is a permissions answer, not a connectivity one, so the network side is working.

1. The share permissions and the NTFS permissions are separate, and the stricter one wins. A folder shared with Everyone can still refuse you at the file system level.
2. You are connecting as the wrong user. Clear saved credentials as in 0x8007052E.
3. You are trying to reach an administrative share such as C$, which requires an administrator account on the target.

No error, no code, just nothing there. If Windows cannot see other computers on the network at all, this is the section to read. This is the most common complaint of all and it has a short list of causes.

1. Network profile is Public. Check both PCs. A Public PC hides itself and does not look for others.
2. Discovery services are stopped. fdPHost, FDResPub and SSDPSRV, all three, on both machines.
3. Network discovery is off in Advanced sharing settings.
4. Different subnets. Discovery uses multicast, which does not cross subnets. A PC on the 2.4GHz guest network and one on the main network cannot see each other, even in the same house. Guest Wi-Fi networks and some mesh systems also block device to device traffic entirely, on purpose.
5. The router blocks multicast. Some routers have "AP isolation", "client isolation" or "wireless isolation" enabled by default, which stops devices seeing each other while the internet works perfectly.

An empty Network folder does not mean sharing is broken. Type \\PC-NAME or \\192.168.1.42 into Explorer directly. If that opens, only the browsing list is broken, and that is a much smaller problem.

You turn network discovery on, click save, come back and it is off again. This is not a bug and it is not your imagination.

The setting depends on those three services. If they are not set to start automatically, the switch has nothing to hold on to and reverts. Set them to Automatic, then turn discovery on:

Set-Service fdPHost -StartupType Automatic
Set-Service FDResPub -StartupType Automatic
Set-Service SSDPSRV -StartupType Automatic
Start-Service fdPHost, FDResPub, SSDPSRV

Run that in PowerShell as administrator. Then set discovery on again, and it will stay.

If nothing on your network changed and sharing broke anyway, a Windows update is a real possibility. Three changes account for most of it.

SMB1 is gone

Windows 11 does not install the SMB1 client at all. Any device that only speaks SMB1 became unreachable the day the PC upgraded. See 0x80070032.

SMB signing is required by default, from Windows 11 24H2

Windows 11 24H2 requires SMB signing on outgoing connections. Devices that do not support signing, which includes a good number of NAS units and Samba servers with older configurations, now fail to connect where they used to work. The visible errors vary and often include 0x8007003B or a plain "not accessible".

The right fix is to enable SMB signing on the other device, which most modern NAS firmware supports. If that is impossible, the requirement can be relaxed, and doing so weakens protection against an attacker tampering with traffic on your network.

Guest access stays blocked

Covered above. It has been the default since Windows 10 1709 and Windows 11 did not soften it.

This looks strange and is usually simple: the two settings are per machine, and you have only fixed one machine.

Being able to see another PC and being able to be seen are different things. A PC with a Public profile, or a blocking firewall, can still browse out to everybody else while remaining invisible and unreachable itself. So the PC that cannot be reached is the one to change, even though it is the other one that shows the error.

A quick way to tell which machine to work on: from PC A, run Test-NetConnection -ComputerName B -Port 445. If it fails, the problem is on B, whatever the error message on A implies.

Usually true, and there is still a cause. The realistic list:

• A Windows update changed a default. See what Windows 11 changed.
• The router was restarted and handed out different addresses, so a mapped drive pointing at a fixed IP now points at a different device.
• Windows reclassified the network as Public. This happens after some driver updates and after certain router changes, silently.
• An antivirus update installed or re-enabled a firewall module.
• A password changed on the other PC, and Credential Manager is still trying the old one. See 0x8007052E.

All of the above is Windows file sharing: powerful, and unforgiving of one wrong setting on either machine.

HearthWire is our free app that connects the computers in your home without touching most of it. It finds the other PCs itself, sends messages and files, shares folders, and includes the Fix my network button described at the top of this page, which repairs the network profile, the firewall rules it needs and the three discovery services in one administrator prompt.

It is honest about its limits, so: it does not change guest policy, SMB signing or your saved credentials, and it will not make an SMB1 only NAS reachable. Those remain manual, and this page is how to do them.

See what HearthWire does