Consider the following scenario:

• You lock and then unlock a Windows Vista-based client computer.
• You try to access network resources.

In this scenario, you may be prompted for user credentials.

Note: This problem does not occur on a Windows XP-based client computer.

Consider the following scenario. You develop an application that calls the CoGetClassObjectFromURL function to install an ActiveX control. A user who has the typical user rights and the typical permissions runs the application on a Windows Vista-based computer. In this scenario, you expect that the user can install an ActiveX control. However, the user is prompted to enter administrative credentials when the user tries to install an ActiveX control. Therefore, a user who does not have administrative credentials cannot install an ActiveX control.

Consider the following scenario:

• You log on to an Active Directory domain from a Windows Vista-based client computer.
• You try to access a business application that is configured to use the Single Sign-On (SSO) feature.

Note: If the application is configured to use the SSO feature, you can access the application without typing your user credentials.
In this scenario, you are prompted to type your user credentials. If you do not enter your credential, you cannot access the application.

This problem occurs if the following conditions are true:

• The user account that you use is a member of the local Administrators group.
• On the Windows Vista-based computer, the User Account Control (UAC) feature is turned on.

When you use Windows Internet Explorer to access files on a Web Distributed Authoring and Versioning (WebDav) site on a Windows Vista-based computer, you receive a dialog box that prompts you to type your user credentials.

Note: A SharePoint Portal Server site is an example of a WebDav site.

This problem occurs if you disable the Automatically detect settings option in Internet Explorer. For information about how to enable this option, see the “More Information” section.

Note: This problem does not occur in Windows XP.

Windows Vista Home Basic, Windows Vista Home Premium, and Windows Vista Starter save user credentials only for the current session. The credentials are not saved if a program tries to save the credentials beyond the current session.

When you create a network connection that automatically calls another connection in Windows Vista, incorrect credentials appear when Windows Vista tests the connection.

Note: This kind of connection is known as a double-dial connection. For more information about this kind of connection, see the “More Information” section.

When Windows Vista tests the connection, incorrect credentials appear in the User name box and Password box of the network connection on which the double-dial connection depends.

You expect the credentials that you saved for the initial network connection or for the Internet connection to appear in the User name box and Password box of the initial network connection or of the Internet connection. However, the credentials that you configured for the double-dial connection, such as for a virtual private network (VPN) connection, appear instead.