Fix 0X0000010E: Primary Transport Connect Failed

You're sitting at your desk, hit Print, and nothing happens. Then you check the error: STATUS_PRIMARY_TRANSPORT_CONNECT_FAILED (0X0000010E). This usually shows up when you're trying to print to a network printer — a Brother HL-L2370DW, an HP LaserJet Pro M404, something shared across the office. Or it pops up when you're mapping a network drive to a Samba share on a Linux server or a Synology NAS. The trigger is almost always the same: Windows can't finish the TCP handshake to whatever device you're connecting to. The printer or NAS is powered on, but the link is dead.

Why Does 0X0000010E Happen?

Root cause is boring but specific. Your PC has a cached IP address or port number for the device. That device changed its IP — maybe the router's DHCP reassigned it, maybe someone rebooted the device. Or the device is on a different subnet now. Windows tries to connect using the old info, the TCP SYN packet goes out but never gets a SYN-ACK back. After a timeout, the kernel spits back STATUS_PRIMARY_TRANSPORT_CONNECT_FAILED.

Another common cause: the printer's network interface is in a half-connected state. It's powered on, but its TCP/IP stack is hung. Happens a lot with printers that go to sleep and wake up slowly. The real fix isn't restarting your PC — it's clearing the stale connection data and forcing a fresh handshake.

Step-by-Step Fix

Power-cycle the printer or NAS. Unplug it from power for 30 seconds. This forces the network interface to fully reset. Don't just press the power button — that doesn't always clear the TCP stack. After plugging it back in, wait 2 minutes for it to fully boot. You should see the network status light turn solid green.
Open a Command Prompt as administrator. Press the Windows key, type cmd, right-click Command Prompt, and select "Run as administrator." If you skip this, some commands won't work.
Flush the DNS cache. In the command prompt, type:
```
ipconfig /flushdns
```
Hit Enter. You should see "Successfully flushed the DNS Resolver Cache." This clears any stale IP-to-hostname mappings your PC is holding onto.
Reset the TCP/IP stack. Type:
```
netsh int ip reset
```
Hit Enter. This rewrites the TCP/IP registry keys. After it finishes, you'll see "Resetting OK!" several times. You don't need to restart yet — we're still cleaning up.
Clear the ARP cache. Type:
```
arp -d *
```
Hit Enter. This deletes all cached IP-to-MAC address mappings. Without this, Windows might still try to reach the old MAC address for the device's IP, even after a reboot.
Restart the Print Spooler service. Type:
```
net stop spooler && net start spooler
```
Hit Enter. You'll see "The Print Spooler service is stopping" and then "The Print Spooler service was started successfully." This clears all pending print jobs and resets the spooler's network port connections.
Now restart your PC. Type shutdown /r /t 0 and hit Enter. Your computer will restart immediately. Don't skip this — the TCP stack reset and ARP cache clear need a fresh boot to take effect.
After the restart, verify the device's IP address. On the printer's control panel, go to Settings > Network > TCP/IP. Write down the IP. On a Synology NAS, go to Control Panel > Network > Network Interface. Make sure that IP matches what you have in Windows. If it doesn't, you need to update the printer port in Windows.
Update the printer port in Windows. Open Control Panel > Devices and Printers. Right-click your printer > Printer Properties > Ports tab. If you see a checkmark next to a WSD port or an old IP, remove it and add a Standard TCP/IP Port. Enter the correct IP address you verified in step 8. Click OK. Then try printing a test page.

What If It Still Fails?

If the error comes back after these steps, you've got a deeper issue. Check three things:

Firewall on the printer or NAS. Some printers have a built-in firewall that blocks pings or raw TCP connections. Log into the printer's web interface (type its IP into a browser) and look for Security > Firewall. Make sure "Allow ping" and "Allow LPR or RAW printing" are enabled. Disable the firewall temporarily to test.
Subnet mismatch. If your PC is on 192.168.1.x and the printer is on 192.168.0.x, they can't talk. They need to be on the same subnet unless you have a router configured to forward between them. Check your PC's IP with ipconfig and compare the first three octets.
Driver corruption. Rare, but it happens. Uninstall the printer completely from Devices and Printers — right-click and Remove Device. Then download the latest driver from the manufacturer's site and reinstall. Don't use the one Windows Update suggests; it's often a stripped-down version that causes this exact error.

I've seen this error on Windows 10 22H2 and Windows 11 23H2. The steps above fix it 9 times out of 10. The 10th time is usually hardware — a dead Ethernet port on the printer or a flaky USB-to-Ethernet adapter on the NAS. Replace the cable before you replace the device.