Fix IP Conflict Error 0XC0000255 on Windows

Quick answer: Run ipconfig /release then ipconfig /renew from an admin command prompt. If that fails, use netsh int ip reset and reboot.

Why You're Seeing 0XC0000255

I've seen this error pop up on Windows 10 and 11 machines more times than I can count. Usually it happens after you plug into a corporate network that has strict DHCP reservations, or when someone's set a static IP on their laptop and forgot. The system tries to grab an address that's already in use, and Windows throws up this error code instead of just silently breaking your connection.

The real trigger? Most common scenario: you just connected to a guest Wi-Fi at a hotel or conference, and two devices got handed the same lease from a misconfigured router. But it also happens when you switch from Ethernet to Wi-Fi without fully disconnecting the cable first.

Fix It in 4 Steps

Skip the router reboot for now. These commands will fix it in 90% of cases without touching the router.

Open Command Prompt as Administrator
Press Win + X, click Terminal (Admin) or Command Prompt (Admin). If you don't see it, search for "cmd" and right-click to run as admin.
Release your current IP
Type ipconfig /release and press Enter. This drops your current lease.
Renew for a fresh IP
Type ipconfig /renew and wait up to 10 seconds. If it hangs, you have a deeper DHCP issue.
Flush DNS and reset winsock
Run these commands one after the other:
```
ipconfig /flushdns
netsh winsock reset
netsh int ip reset
```
Then reboot your machine. The IP conflict should be gone.

If That Doesn't Work

Sometimes the router is the problem. I've seen consumer routers (especially older Netgear and Linksys models) get stuck in a bad lease table. Power cycle the router by unplugging it for 30 seconds. Then try the commands again.

Still no luck? Check for a static IP you might have set manually. Go to Settings > Network & Internet > Wi-Fi (or Ethernet) > Manage known networks > Properties. If you see "IP assignment" set to Manual, switch it back to Automatic (DHCP). A lot of people forget they set a static IP when they were troubleshooting something else and never undid it.

Prevent This From Happening Again

Two things I always tell my users:

Never set a static IP on a laptop unless you absolutely have to (and if you do, write it down so you can revert).
If you're on a corporate network, ask your IT team to enable DHCP reservations for your MAC address. That way you always get the same IP but it's managed centrally.

In most cases, the ipconfig /release and renew combo is all you need. If you're still stuck after trying these steps, it's time to check if your network adapter driver is corrupted. Run sfc /scannow in an admin command prompt to be sure.