Microsoft Windows Registry Guide, Second Edition

Getting User Profiles

How users get their profiles depends on the type of profile you've configured their accounts to use:

• Local user profile.

  This profile is created the first time users log on to their computers. Local user profiles are stored on the local hard disk. Changes that users make to their profiles don't follow them from computer to computer.

• Roaming user profile.

  This profile is available to users from any computer on the network, and changes that users make to their profiles follow them from computer to computer.

• Mandatory user profile.

  This profile is similar to roaming user profiles. Administrators assign mandatory user profiles to users, and Windows throws away users' changes when they log off the operating system. In other words, users start with the same settings every time they log on to the operating system. Microsoft provides mandatory user profiles to provide compatibility with Windows NT 4.0, but you should consider using Group Policy instead.

The following sections describe how Windows creates a profile when users log on to the operating system. The section “Using Roaming User Profiles” describes how to create and manage roaming user profiles. Also, the section “Managing Roaming User Profiles” shows you how to prevent Windows from merging the local copy of a profile with the server copy by using Group Policy.

Local Profiles

Here's an overview of how Windows creates and uses a local user profile for users the first time they log on to their computers:

1. The user logs on to Windows.

2. Windows checks the list of user profiles in the key ProfileList to determine if a local profile exists for the user. If an entry exists, the operating system uses it; otherwise, the operating system does one of the following:

   • If the computer is a domain member, Windows checks the NETLOGON share on the domain controller for a default user profile in a subfolder named Default User. If it exists, the operating system copies NETLOGON\ Default User to %SystemDrive%\Documents and Settings\Username, where Username is the name of the user's account.

   • If the computer is not a domain member or if Windows doesn't find a default user profile on the NETLOGON share, it uses the local default user profile. It copies %SystemDrive%\Documents and Settings\Default User to %SystemDrive%\Documents and Settings\ Username.

3. Windows loads the profile hive NTUSER.DAT into HKU and links the root key HKCU to it.

When the user logs off Windows, the operating system saves any changes to the profile in the user profile folder. It doesn't copy the profile folder to the network. It also unloads the profile hive from the registry.

Roaming Profiles

Here's an overview of how Windows creates and uses a roaming user profile for users the first time they log on to their computers:

1. The user logs on to Windows.

2. Windows checks the list of user profiles in the ProfileList key to determine whether a local profile exists for the user. If an entry exists, the operating system merges the network copy of the profile into the local profile folder; otherwise, the operating system does one of the following:

   • Windows checks the NETLOGON share on the domain controller for the Default User folder. If the folder exists, the operating system copies the Default User folder to %SystemDrive%\Documents and Settings\Username, where Username is the name of the user's account.

   • If Windows doesn't find a default user profile on the NETLOGON share, it copies %SystemDrive%\Documents and Settings\Default User to %SystemDrive%\Documents and Settings\Username.

3. Windows loads the profile hive NTUSER.DAT into HKU and links the root key HKCU to it.

When users log off Windows, the operating system saves their changes to the local profile folders and then unloads the profile hives from HKU. Afterward, the operating system copies their profile folders to the network location specified by the administrator. If the profile folder already exists on the network, the operating system merges the local copy into the network copy. For more information, see “Understanding the New Merge,” later in this chapter.

NOTE

There are two differences between roaming and mandatory user profiles. First, you create the mandatory profile and copy it to the user's profile folder instead of allowing Windows to create it when the user logs on to the computer. Second, you rename the NTUSER.DAT to NTUSER.MAN. Windows uses the .MAN file extension to make the profile mandatory. Windows doesn't merge mandatory user profiles to the network when the user logs off the computer.