Disconnecting Null Session Disconnects Normal Sessions Too (101721)


The information in this article applies to:

  • Microsoft Windows NT Server 3.1
  • Microsoft Windows NT Workstation 3.1
  • Microsoft Windows NT Advanced Server 3.1
This article was previously published under Q101721

SUMMARY

If Server Manager is run on a server, a particular client has both normal and null sessions connected to that server, and the client has files opened over the normal session, telling Server Manager to disconnect the null session disconnects both sessions with no warning about the open files.

RESOLUTION

Be very careful when disconnecting null sessions. If you really need to disconnect \\CLIENT from \\SERVER, disconnect all normal (non-null) sessions first. This will give you the appropriate warnings about open files.

MORE INFORMATION

Two types of sessions can be established between computers. Normal sessions have a user name and computer name associated with the client, and file operations occur over normal sessions. Null sessions have only a computer name (no user name), and null sessions are used for administrative purposes.

Steps to Reproduce Problem

Assume that \\CLIENT has both normal and null sessions established with \\SERVER. Also assume that \\CLIENT has one or more files opened over the normal session, but no files opened over the null session.

  1. Run Server Manager and choose Properties from the Computer menu for \\SERVER, and choose Users.
  2. Select the null session in the Connected Users area. The null session has a blank User column.
  3. Choose Disconnect. You will get the following warning:
    Are you sure you want to disconnect USER from all connected resources?
Choosing Yes will disconnect \\CLIENT from \\SERVER, closing any open files. Note that the warning makes no mention of open files.
Modification Type:MajorLast Reviewed:11/20/2003
Keywords:kbnetwork KB101721
©2003 Microsoft Corporation. All rights reserved.