Data Encryption Causes RAS NetBIOS Error 640 Error Message

 Last reviewed: September 9, 1996
Article ID: Q132169
The information in this article applies to:
  • Microsoft Windows NT Workstation versions 3.5 and 3.51
  • Microsoft Windows NT Server versions 3.5 and 3.51
  • Microsoft Windows for Workgroups version 3.11

SYMPTOMS

If you attempt to connect to a Windows NT 3.5 or 3.51 RAS server with a Windows for Workgroups 3.11 RAS client, and you have selected Require Data Encryption, the following error appears: 

   NETBIOS error 640: a netbios error has occurred
   (with failed code 0xa)

CAUSE

Windows for Workgroups version 3.11 was released before the development of RAS data encryption in Windows NT version 3.5 and 3.51. Because Windows for Workgroups RAS cannot negotiate this encryption it displays the error.

For information on other causes of Error 640, see the following article in the Microsoft Knowledge Base: 

   ARTICLE-ID: Q111094
   TITLE     : RAS ErrMsg: NETBIOS Error 640: A Netbios Error Has
               Occurred...

WORKAROUND

Disable the "Require data encryption" option under the Encryption settings in the Network Configuration dialog of the Remote Access Setup window. Click Configure after you select Remote Access Service in Control Panel Network to view the Network Configuration dialog.

KBCategory: kbinterop kberrmsg
KBSubCategory: ntras ntsecurity
Additional reference words: 3.50 3.51 prodnt 3.11 wfw wfwg access denied



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Last reviewed: September 9, 1996
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