Troubleshooting dial-up modem error codes

Error 691	Error 680	Error 645
Error 718 / 721	Intermittent disconnection

Error 691 - Access denied because username and/or password is invalid on the domain
This problem tends to be a problem during the authentication process.

• The main reason for this is an incorrect username or password. Bear in mind these are both case-sensitive and the username must be lower case.
  
• Make sure you are dialling the correct dial-up number. NOTE: NTL accounts will not accept the 1470 prefix.
  
• Check your connection settings to ensure that Tiscali is set to default and the following settings are NOT selected: LAN settings, automatic configuration script and proxy server.
  
  
• Check that the connection settings have been set to Security setting typical to allow unsecured password. The only networking protocol required her is TCP/IP and ensure that Internet Connection Sharing has not been enabled (we only support stand-alone consumer connections)
  
  
• Make sure logon to network is not selected
  
• Recreate the dial-up connection as indicated HERE
  
• Ensure no firewall modification or software updates have occurred since receiving the problem

Error 680 No dial tone
This problem tends to occur between the modem and the phone line

• Make sure your telephone line is connected to your modem. Insert one end of the telephone wire into the wall socket and the other end into the back of the modem. When connecting the telephone line to the back of the modem, select the socket marked "Line" or "Telco".
  
• Unplug all other devices attached to the telephone line ( e.g. personal answering machine), and make sure your telephone receiver is on the hook.
  
• If you have a call minder or answering service, check and clear your new messages. This occurs because the call minder gives a series of tomes to tell you you have new messages which can sometimes interfere with the modem dial tone
  
• Run modem diagnostics which are available from the modem icon in the control panel to ensure your modem is responding
  
  
  
  
• Restart your PC
  
• Attempt dialling from your handset to the intended number excluding the 1470. If you cannot establish a connection this indicates a problem with your phone line. If it connects it indicates a problem with your PC or modem.
  
• Reinstall the modem using the modem providers software

Error 645 Internal Authentication Error
This problem tends to occur between the customers modem and the phone line

• This error can occur if the Require encrypted password option is enabled on the Server Types tab in the connection's properties, or an incorrect user name or password have been entered
  
• This error has been known to occur when setting up a Virtual Private Network (VPN) connection in Win 98/ME. Check this by going into Internet Properties and then selecting the Connections tab and then verifying that the settings are correct (see Connection Settings for reference)
  
• Recreate the Dial up Connection
  
• Ensure that Dial-up Adaptor exists in the Network Components available in the Network settings accessible in the Control Panel
  
• If this does not resolve the problem reinstall the modem

Error 718/721 PPP Error
This problem tends to occur due to failure of the modem synchronising with the local exchange

• Recheck connection settings, as this error can be caused by dialling an incorrect number
  
• Restart your PC and attempt to reconnect as this can sometimes be caused by a synchronisation problem
  
• Recreate the Dial-up Connection
  
• Test the line connectivity by dialling the Internet Dial-Up number directly from your phone handset
  
• If this problem has been ongoing for a long period an upgrade or repair of the modem drivers is required in case the modem drivers have corrupted.

Intermittent disconnection
This problem tends to occur between the modem and the phone line

• Make sure you do not have any other services on the phone line such as call waiting
  
• Ensure there has been no automatic disconnect set up on your system. This can be checked in Win 2000 and Win XP in the internet options, select the connection settings then properties, in the options tab ensure the Idle time before hanging up is set to never. In Win 95/98/ME this can be found by right clicking the connection in Dial Up Networking and selecting properties, then configure and then selecting Connections and deselecting Disconnect a call if at idle for x minutes
  

Check your modem setup
Check your Dial up Settings
Test your phone line
Common Error Codes
Reinstall your modem drivers
Recommended modems

• How can I protect myself from online fraud?
• How to deal with and avoid spam.

"When connecting to Tiscali as your ISP, you need to use Tiscali's SMTP server to send email: smtp.tiscali.co.uk"

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