Docstoc

Control

Document Sample
Control Powered By Docstoc
					                        Control, Alt, Delete
 HOW TO: Enable or Disable the CTRL+ALT+DELETE Sequence for Logon

This describes how to enable or disable the CTRL+ALT+DELETE sequence for logging
on in Windows XP.

You can require users to press CTRL+ALT+DELETE before logging on to a Windows
XP-based computer, or you can eliminate this requirement for a faster logon process.
Note that you must be logged on with Administrator rights to perform this task.

To Enable or Disable the CTRL+ALT+DELETE Sequence

1. Click Start, click Control Panel, and then click User Accounts.
2. Click the Advanced tab.
3. In the "Secure logon" section, select or clear the "Require users to press
Ctrl+Alt+Delete" check box.

Troubleshooting

- Disabling the CTRL+ALT+DELETE sequence creates a "security hole." The
CTRL+ALT+DELETE sequence can be read
  only by Windows, ensuring that the information in the ensuing logon dialog box can be
read only by Windows. This can
  prevent rogue programs from gaining access to the computer.

- If a Windows XP-based computer is part of a domain, domain-wide policies may have
been set that override the settings
   you make on the local computer.

- On MS-DOS-based computers (and some older UNIX-based systems), pressing
CTRL+ALT+DELETE gains the
  attention of the BIOS, causing a "warm" reboot. You can use the keyboard to shut
down the operating system. On
  Windows-based computers (starting with Microsoft Windows NT), the
CTRL+ALT+DELETE sequence is intercepted by
  Windows. The advantage of the keystroke-intercept technique is to help prevent
Windows from being shut down by
  someone who does not have access to do so.

    Lock Your Computer and Use Other Windows Logo Shortcut Keys

This describes how to quickly lock your computer as well as the other Windows logo
shortcut keys that you can use.
Windows XP includes a new Microsoft Natural Keyboard shortcut to lock your computer.
Any other compatible keyboard that includes the Windows logo key and the Application
key can also perform this task.

To use this shortcut, press the Windows logo key+L. The following list has different
computer lock-up scenarios that are available to you, as well as other ways to lock the
computer:

Fast User Switching Enabled

If the Fast User Switching feature is enabled and you lock the computer, you can
observe the same behavior as if you switched users: The computer returns to the
Welcome screen and other users can log on to the computer.

Fast User Switching Disabled

If the Fast User Switching feature is disabled and you lock the computer, the Unlock
Computer dialog box is displayed that requires the current logged-on user to enter a
password to unlock the computer.

Welcome Screen Enabled

If the Welcome screen is enabled, the computer can also be locked if you press
CTRL+ALT+DELETE (to open Task Manager), and then click Lock Computer or click
Switch User on the Shut Down menu.

NOTE: The ability to observe "Lock Computer" or "Switch User" on the Shut Down
menu is dependent upon whether or not the Fast User Switching feature is enabled.

Welcome Screen Disabled

If the Welcome screen is disabled, you can lock the computer if you press
CTRL+ALT+DELETE, and then click Lock Computer in the Windows Security dialog
box.

In all of the preceding scenarios, the "Windows logo key+L" shortcut can lock the
computer. If you do not have a password that is set for your user account, anyone can
unlock your computer. To set a password for your user account: In
Control Panel, double-click User accounts, select your user account, and then click
"Create a password".

                                                     Windows logo key+BREAK
Windows logo key - Display Windows logo key+L - Lock
                                                     Display the System
or hide the Start menu     the computer
                                                     Properties dialog box
Windows logo key+D Show Windows logo key+M           Windows logo key+SHIFT+M
the desktop                Minimize all windows      Restore minimized windows
Windows logo key+E Open       Windows logo key+F             CTRL+Windows logo key+F
My Computer                   Search for a file or folder    Search for computers
Windows logo key+F1           Windows logo key+R Open        Windows logo key+U Open
Display Windows Help          the Run dialog box             Utility Manager

   Pressing CTRL+ALT+DEL & Cancel Appears to Disconnect Session

While you are using Terminal Services Advanced Client in Full-Screen mode, if you use
the CTRL+ALT+DELETE key combination to lock the session, and then you click
Cancel, this appears to disconnect the Terminal Services session.

This problem is caused by the behavior of Terminal Services Advanced Client, which is
an ActiveX control. The control becomes independent of the Microsoft Internet Explorer
shell during full-screen activation. In some scenarios (such as ALT+TAB,
CTRL+ALT+DELETE, or in a multiple-monitor environment), if you switch to the Internet
Explorer window that is hosting the control, it appears to host a blank control.

To resolve this problem, you can restore the session by clicking the Full-Screen icon at
the bottom of the screen, or press ALT+TAB to switch back to the Terminal Services
session. When you press ALT+TAB, you can switch between active programs.

Here is sample scenario of when this problem may occur:

1. Start a Terminal Services Advanced Client session.
2. Press CTRL+ALT+BREAK to put the session in Full-Screen mode.
3. Press CTRL+ALT+END to lock the session.
4. Press CTRL+ALT+DELETE.
5. Click Cancel.
6. The Internet Explorer page appears blank.
7. The session appears to be disconnected.

In this scenario, the session is not actually lost. You can restore it by using the methods
described in the "Resolution" section in this article.

            Administrator Unable to Unlock a "Locked" Computer

After you restart a computer running Windows and no one has logged on, you may be
unable to log on to the computer either locally or to the domain.

The following error message may be displayed at logon:

This computer is in use and has been locked. Only or an administrator can unlock this
computer. Press Ctrl + Alt + Del to unlock this computer.

If you try to unlock the computer, the following error message may be displayed:
This computer is locked. Only or an administrator can unlock this computer.

If a user has logged on and logged off, you may be unable to log on to the computer
(locally or to the domain) and the following error message may be displayed:

This computer is in use and has been locked. Only <domain>\<username> or an
administrator can unlock this
computer. Press Ctrl + Alt + Del to unlock this computer.

If you try to unlock the computer, the following error message may be displayed:

This computer is locked. Only <domain>\<username> or an administrator can unlock
this computer.

NOTE: In the error messages above, <domain> is the domain name of the last user
who logged on to the server and <username> is the name of the user who last logged
on to the server.

This behavior can occur for either of the following reasons: When the default screen
saver is set to use a non-existent screen saver program. When you use a corrupted
screen saver that is password protected.

To resolve this problem, use another screen saver program (such as Logon.scr) that is
installed locally on the system or that is not corrupted.

1. Start Registry Editor (Regedt32.exe).
2. Locate the Scrnsave.exe value under the following registry key:

           HKEY_USERS\.Default\Control Panel\Desktop

3. On the Edit menu, click String, type "logon.scr" (without the quotation marks), and
then click OK.
4. Locate the ScreenSaverIsSecure value.
5. On the Edit menu, click String, type "0" (without the quotation marks), and then click
OK.
6. Quit Registry Editor.

WORKAROUND

To work around this problem, use the appropriate method.

Method 1: When the Error Message States the Computer Is Locked by
<domain>\<username>

1. Press CTRL+ALT+DELETE to unlock the computer.
2. Type the logon information for the last logged on user, and then click OK.
3. When the Unlock Computer dialog box disappears, press CTRL+ALT+DELETE and
log on normally.

Method 2: When the Error Message Does Not State Who Locked the Computer

1. Use the Shutdown tool in the Microsoft Windows Resource Kit and attempt to shut
down the locked computer. The
   System Shutdown dialog box is displayed on the locked computer, but the computer
does not restart.
2. When the shutdown timer expires, the "Welcome to Windows" dialog box is
displayed.
3. Before the screen saver becomes active, press CTRL+ALT+DELETE, and log on
normally.

NOTE: If you do not use one of these methods to log on, you must restart the computer
and log on before the screen saver program starts.

				
DOCUMENT INFO
Tags:
Stats:
views:2
posted:2/17/2012
language:
pages:5