How do I check for ‘static IP duplication’ as a possible cause?

If there is no change in the first step, compare the ‘modem/router and PC restart’ in order. If symptoms disappear immediately after certain actions or the conditions for their occurrence change, this can be an important clue in narrowing down the cause.

IP address conflict message or internet instability: When do I need a professional check?

Even if you follow the above solution steps in order, if the IP conflict symptom repeats or hardware abnormal signals such as a burning smell, abnormal noise, overheating, or failure to recognize parts appear, we recommend backing up important data and then having a professional inspection.

PC FIX

Computer Troubleshooting Guide

Internet

An IP address conflict message appears or the Internet is unstable.

Q: What should I check first if I see symptoms of an IP conflict?

First, proceed with the ‘Compare with other devices on the same network’ step. The first thing to do is to determine whether it is a problem with the PC itself or with the router or ISP. We recommend that you avoid changing multiple settings at once and check to see if your symptoms change after each step.

If “IP conflicts” are repeated, it is better to narrow the scope to fixed IP duplication and DHCP range issues rather than changing several settings at once. Compare with other devices and wired connections to narrow down where the problem occurs: PC, router, or ISP.

Solving Order
We've organized the methods starting with the simplest and least expensive ones. Please check the solutions one by one, starting from the top.

Do you have these symptoms?

IP conflict
same IP address
Internet connection is disconnected

main causes

Static IP redundancy
DHCP scope issues
manual setup

How to solve

Please check them in order from the top. If the issue is resolved, you do not need to proceed to the next step.

Compare with other devices on the same network

The first thing to do is to determine whether it is a problem with the PC itself or with the router or ISP.

Difficulty Easy time 5 minutes cost 0 won

1Try using the same Internet connection on your phone or another PC.
2If all devices do not work, check the modem, router, and ISP first.
3If only one PC is the problem, proceed to the next step.

confirmation point

After these steps, see if your “IP conflict” symptoms decrease or disappear. If there is no change, the possibility of static IP duplication is also checked in the next step.

Restart your modem/router and PC

You can reset the temporary status of DHCP, NAT, and adapter.

Difficulty Easy time 5-10 minutes cost 0 won

1Restart your PC.
2Turn off the router and modem for about 30 seconds and then turn them back on.
3Wait until the connection is stable.

Reset IP/DNS status

It can troubleshoot TCP/IP or DNS cache issues.

Difficulty Moderate time 10-15 minutes cost 0 won

1Run netsh winsock reset in the administrator terminal.
2Execute in this order: netsh int ip reset, ipconfig /release, ipconfig /renew, and ipconfig /flushdns.
3Restart your PC.

Update or reinstall network drivers

Outdated or corrupted network drivers can cause the symptom.

Difficulty Moderate time 10~30 minutes cost 0 won

1Check the device in Device Manager.
2Check your PC or component manufacturer's site for network drivers for your current model.
3If the problem started immediately after an update, consider rolling back to the previous stable version.
4After installing the driver, restart your PC.

Check VPN, proxy, firewall and network initialization

A virtual adapter or filter driver may be blocking your path to the Internet.

Difficulty Moderate time 15-30 minutes cost 0 won

1Turn off the VPN/proxy for a moment and compare.
2Check recently installed network security programs.
3As a final step, consider a Windows network reset.

Frequently Asked Questions

We've put together a list of things we frequently check regarding this issue.

Related issues

If the symptoms do not match exactly, please check the issue below.

Internet

Internet not working after Windows update

If “No internet after update” repeats, it is better to narrow the scope to updated network drivers and changes to TCP/IP settings rather than changing several settings at once. Compare with other devices and wired connections to narrow down where the problem occurs: PC, router, or ISP.

View solutions →

Internet

Internet not working after turning on or off VPN

If “No Internet after VPN” repeats, it is better to narrow the scope to virtual adapter, DNS, routing settings, and kill switch rather than changing several settings at once. Compare with other devices and wired connections to narrow down where the problem occurs: PC, router, or ISP.

View solutions →

Internet

Connected to network but shows limited or no internet

If you are seeing “limited connection” symptoms, possible causes include DHCP/gateway issues, router/ISP, etc. Compare with other devices and wired connections to narrow down where the problem occurs: PC, router, or ISP.

View solutions →

Internet

Computer suddenly unable to connect to internet

When troubleshooting a computer that suddenly fails to connect to the Internet, it is important to rule out the causes one at a time. Based on the “No Internet” symptom, check the router/modem or ISP problem and the network adapter/IP/DNS settings, then proceed to the next step. Compare with other devices and wired connections to narrow down where the problem occurs: PC, router, or ISP.

View solutions →

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