Troubleshooting RAS Client Issues in Windows NT 4.0

This article was previously published under Q162293
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This article contains steps to help you troubleshoot issues with theRemote Access Service (RAS) in Windows NT 4.0. This article focuses onissues that can occur when you use RAS to dial into another computer oran Internet service provider (ISP).

The issues discussed in this article include:
  • Cannot dial with RAS
  • Cannot connect after dialing with RAS

Cannot Dial with RAS

When you attempt to dial with Dial-Up Networking, the following errormessage may appear:
Error 692: Hardware failure in port or attached device.
If you receive this or another error message that indicates that the modemis not working properly, refer to the following articles in the MicrosoftKnowledge Base:
ARTICLE-ID: 161516
TITLE : Troubleshooting Modem Problems Under Windows NT 4.0

ARTICLE-ID: 122839
TITLE : Err Msg: Error 692: Hardware Failure in Port or Attached...
If you have upgraded from Windows NT 3.51 and you are running a programthat monitors the phone line (for example, a fax program), you may receivean error message that indicates the port is busy when you try to dial outwith Dial-Up Networking. For example:
Error 633: The port is already in use or is not configured for Remote Access dial out.
If you installed RAS in Windows NT 3.51 before upgrading to Windows NT4.0, the kernel-mode telephony driver that is used in Windows NT 3.51 isretained and RAS uses non-Unimodem drivers. If another program uses theUnimodem driver and is set answer the line automatically, that programcauses TAPI 2.0 to control the communications port. When this occurs, thecommunications port is not available to the non-Unimodem version of RAS.

To resolve this problem, remove the non-Unimodem driver and replace itwith one supplied with Windows NT 4.0. To do so, follow theses steps:
  1. In Control Panel, double-click Network.
  2. Click the Services tab.
  3. Click Remote Access Service, and then click Properties.
  4. If the type of modem listed indicates that the kernel-mode TAPI driver is still being used [that is, it lists the type as "Modem (modem.inf)"], click the port, and then click Remove.
  5. Click Add to add the Unimodem driver (the driver supplied with Windows NT 4.0) for this COM port.
  6. Click Continue and restart your computer when prompted to do so.

Cannot Connect After Dialing with RAS

If the telephone line is unusually noisy, you may receive an error messagesuch as:
Error 640: A Netbios error has occurred.
This message indicates that the modem may not be able to negotiate aconnection at a higher speed. Try setting the modem speed on the clientcomputer down to a lower speed such as 9600 bps. To do so, follow thesesteps:
  1. In Dial-Up Networking, click the appropriate phone book entry.
  2. Click More, and then click Edit Entry And Modem Properties.
  3. Click the appropriate modem, and then click Configure.
  4. In the Initial Speed box, click 9600, and then click the Enable Modem Compression check box to clear it.
  5. Click OK.
  6. Click the Server tab, click the Enable Software Compression check box to clear it, and then click OK.
If the RAS server does not answer or you cannot connect, test theconnection from another computer. If you cannot connect using anothercomputer, there may be a problem with the RAS server. Contact your networkadministrator for assistance.

If you can connect to the RAS server from another computer, there may be ahardware compatibility problem with your modem. Check the Windows NTHardware Compatibility List (HCL) to see if your modem is listed. Forinformation about where to obtain the HCL, see the following article inthe Microsoft Knowledge Base:
ARTICLE-ID: 131303
TITLE : Latest Windows 2000 and Windows NT Hardware Compatibility List (HCL)
If your modem is not listed, contact the modem's manufacturer or considertrying a supported modem.

Article ID: 162293 - Last Review: 01/10/2015 11:07:46 - Revision: 1.1

Microsoft Windows NT Server 4.0 Standard Edition, Microsoft Windows NT Workstation 4.0 Developer Edition

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