PPPoE Error 678 — What It Means & How to Fix It

What Does This Error Mean?

Error 678 means your computer tried to connect to your ISP but got no response. Think of it like calling someone on the phone — the line rings, but nobody picks up. Your modem or the ISP's equipment is not responding to the connection request.

Affected Models

Windows XP
Windows Vista
Windows 7
Any DSL broadband connection
Any PPPoE internet connection

Common Causes

The modem is not detecting a signal from the phone line or cable
Your ISP has an outage or network maintenance in progress
The DSL filter is missing, damaged, or installed on the wrong phone socket
The phone line cable between the modem and the wall socket is damaged
The modem itself has failed or overheated

How to Fix It

Restart your modem completely. Unplug the power cord, wait one full minute, then plug it back in. Wait for all lights to stabilize before trying to connect.

This is the fastest first step and fixes the issue more than 50% of the time.
Check the phone cable from your modem to the wall. Try a different cable if you have one.

A damaged or low-quality phone cable is a surprisingly common cause.
If you have a DSL filter installed, check that it is correctly plugged in. Try removing it temporarily and connecting directly.

A faulty DSL filter can block the modem from syncing with your phone line.
Check your ISP's website or app for any service outages in your area.

Planned maintenance often happens overnight and may still be in progress.
Try connecting the modem to a different phone socket in your home if one is available.

Internal house wiring faults can affect signal quality on specific sockets.

When to Call a Professional

If you have tried all the steps below and still get Error 678, call your ISP's technical support. Ask them to run a line test and check for signal issues at the exchange. They may need to send a technician to inspect your phone line or connection point.

Frequently Asked Questions

Is Error 678 the same as Error 651?

They are similar but different. Error 678 means the remote server is not responding at all. Error 651 means the modem itself is not communicating properly with your PC. Both can look the same from the outside but have different root causes.

Can bad weather cause Error 678?

Yes, on DSL (phone line) connections it can. Heavy rain and flooding can affect underground phone cables. This reduces signal quality or drops it entirely, causing Error 678. If the weather is bad and you suddenly lose connection, wait for it to clear.

How long should I wait before calling my ISP?

If a modem reboot does not fix it, wait 30 minutes and try again. If the error persists for more than an hour, call your ISP. Have your account number ready and let them know you have already tried rebooting.