When you try to connect to the Internet: Error 678 “The remote computer did not respond.”

Causes

• A network cable is disconnected.
• Corrupted modem drivers
• Spyware running on the computer causing interference with the connection.
• Winsock has to be repaired.
• Third-party firewall software is blocking the connection.

Resolution

• Step 1: Make sure that the network cable is connected.
• Step 2: Make sure that the network adapter is enabled.
• Step 3: Reset the modem.
• Step 4: Uninstall and then reinstall the modem and the drivers by using Device Manager.
• Step 5: Create a new DSL or cable connection.
• Step 6: Repair Winsock and TCP/IP.
• Step 7: Temporarily uninstall third-party firewalls.
• Step 8: Scan for and remove spyware and adware.
• Step 9: Clear the temporary Internet files.

Additional Steps:
If the problem continues after you follow the steps in this article, try the following:

• Repair the network connection.
• Renew the IP address.
• Scan for viruses.

When you attempt to connect to your Internet service provider (ISP) and receive Error 691: Access was denied because the user name and/or password was invalid on the domain.

Causes

• The settings for your dial-up connection to your ISP are configured incorrectly.
• The dial-up connection's security option is incorrectly configured to use the required secured password setting.
• Your ISP's Point-to-Point Protocol (PPP) server is not functioning properly.
• You type an incorrect user name or password.

Resolution
To resolve this issue (or issues), use the following methods, as necessary, in the order presented. After you finish each method, check to see whether you can connect to your ISP successfully.

NOTE: You must be logged on as an administrator or a member of the Administrators group to complete these procedures. If your computer is connected to a network, network policy settings may also prevent you from completing these procedures.

Verify Your User Name and Password:
If the problem continues after you follow the steps in this article, try the following procedures. These procedures may help you determine the cause of the problem, or they may resolve the problem.

• Make sure that the CAPS LOCK key has not been accidentally pressed and engaged.
• Click Start, point to Connect To, and then click your dial-up connection.
• In the Connect dialog box, verify that your user name and password are correctly typed in the User name and Password boxes as provided by your ISP, and then click dial. NOTE: If you are not sure what your user name and password are, contact your ISP for assistance.

If you try to establish a Point-to-Point Protocol (PPP) dial-up connection, and receive the following error message- Error 734: The PPP link control protocol was terminated.

Causes

• Multi-link negotiation is turned on for the single-link connection.
• The dial-up connection security configuration is incorrectly configured to use the required secured password setting.

Resolution

• Click Start, point to Settings, and then click Network and Dial-up Connections.NOTE: For Windows Server 2003, click Start, point to Control Panel and then point to Network Connections.
• Right-click the appropriate dial-up networking connection and then click Properties.
• Click the Networking tab and then click Settings.
• Click to clear the Negotiate multi-link for single link connections check box (if it is selected).
• Click OK, and then click OK.
• Double-click the connection and then click Dial.
• If this procedure resolves the issue and you can establish a dial-up connection, you do not have to follow the remaining steps in this article.
• If this does not resolve the issue and you cannot establish a dial-up connection, go to step 7 to continue to troubleshoot this issue.
• Right-click the connection, and then click Properties.
• Click the Security tab.
• Under Security options, click Allow unsecured password in the Validate my identity as follows box, and then click OK.
• Double-click the connection, and then click Dial to verify that you can establish a dial-up connection.

When you try to connect to the Internet by using a Point-to-Point Protocol over Ethernet (PPPoE) connection, you may receive one of the following error messages:

Error 769: The specific destination is not reachable.
OR
Error 769: "Either you specified a destination address that is not valid, or your remote server is down."

Causes
This behavior may occur if the network card in your computer is not turned on (enabled).

Resolution
To resolve this issue, turn on (enable) the network card, and then run the Network Setup Wizard. To do this, follow these steps:

• Click Start and then click Control Panel.
• In Control Panel, click Performance and Maintenance and then click System.
• In the System Properties dialog box, click the Hardware tab and then click Device Manager.
• In Device Manager, click Network adapters.
• On the Action menu, click Enable.
• Quit Device Manager.
• Click Start and then click Control Panel.
• In Control Panel, click Network and Internet Connections and then click Network Connections.
• In Network Connections, click Network Setup Wizard under Network Tasks and then follow the on-screen steps.
• When you complete the steps in the wizard, restart your computer.