MSGINA Features

Following is a list of the standard features and a brief description of how they are controlled:

Registry key values control the availability or behavior of many of the MSGINA features. Unless otherwise noted, these key values belong to a registry key referred to as the Winlogon key and have value types of [REG_SZ]. The actual path of the Winlogon key is:

\HKEY_LOCAL_MACHINE\Software\Microsoft\Windows NT\CurrentVersion\Winlogon

Having [REG_SZ] value types makes it convenient to query the key values using the GetProfileString and GetProfileInt functions.
 
 

Legal Notification Dialog Box

In many countries and states it is legal for anyone to walk up to a system, log on, and begin working unless there are notifications indicating that the system is intended for the private use of authorized users. Also, many users want company-specific messages displayed before normal logon. MSGINA uses two registry key values of the Winlogon key to implement such capabilities. If either key value is present and contains a non-null string, then a Legal Notice dialog box is displayed before the usual Welcome screen. The caption of the dialog box is taken from one of these key values, while its message is taken from the other.

These key value names are:
 
Value Description
LegalNoticeCaption Any string you want displayed as the dialog caption.
LegalNoticeText Any string you want displayed as the dialog body.
 
 
 

Don't Display Last Username

By default, the MSGINA logon screen displays the name of the last user to successfully log on to a computer. To alter this, MSGINA uses a registry key value of the Winlogon key. If this key value is present and contains a string value of 1, no user name is displayed in the logon dialog box.
 

AutoAdmin Logon

This feature allows a Windows NT system to log on a user automatically. This feature can be used in two ways:

1. To enable a user to be automatically logged on exactly once. If the user logs off or the system is shut down, the user will not be automatically logged on afterward. The user must have a null password in order for this feature to be used.

2. To enable a user to be logged on every time the system boots or the user logs off.

This feature uses the following values of the Winlogon key:
 
Value Description
AutoAdminLogon "1" or any other string value.
DefaultUserName The name of the user to automatically log on.
DefaultDomainName The name of the domain that the user account is in.
DefaultPassword The password of the user account, in clear text.

If the AutoAdminLogon key value is present and contains a 1, an automatic logon will occur based on the DefaultPassword key value.

The account being logged onto is specified using the DefaultUserName and DefaultDomainName key values. If present and non-null, the password in DefaultPassword is also used.

If an automatic logon is being performed but the DefaultPassword key value is not present or is null, this is a one-time only autologon. The AutoAdminLogon key value will be set to contain a zero before the logon is attempted. This prevents any future autologons.

There is one additional caveat to autologon. If an autologon is indicated, MSGINA checks the state of the SHIFT key. If it is held down, it is assumed that the user wants to override autologon and provide identification and authentication information interactively. This is a critical feature when you are debugging a dedicated application. The SHIFT override of automatic logon is disabled if the IgnoreShiftOverride key value is present and has a value of 1.
 
 

Allow Unauthenticated Shutdown

You can configure MSGINA to include a Shutdown button in the logon dialog box. This lets users shut down the system without first logging on. Inclusion of this button is controlled by the following key value:
 
Value  Description
ShutdownWithoutLogon "1" to include button; any other value to exclude button.
 
 
 

USERINIT.EXE Activation

USERINIT.EXE is an application activated by MSGINA at user logon time. It runs in the newly logged-on user's context and on the user's desktop. Its purpose is to set up the user's environment. This includes restoring net uses, establishing profile settings (such as fonts and screen colors), and running logon scripts, including those of network providers. It then activates the user shell program(s), which inherit the environment that USERINIT.EXE sets up. The shell programs that USERINIT.EXE activates are listed in the shell value under the Winlogon registry key.

There can be more than one program listed under Winlogon, each separated by a comma. By default, Explorer is listed. If the shell registry value is not found or has no programs listed, Explorer is activated as the default shell.
 
 
 

Logged-On Security Options

When logged on, if a user enters an SAS, the user is presented with a security options screen. Among the options listed are: The provided alternative GINA changes/enhances some of the options when an SAS is provided while a user is logged on.