11.5 HKU

The "U" in HKU stands for "user." That's appropriate, since HKU's subkeys store settings that vary from user to user. Every time a user logs in, one of two things happens. If the user's never logged in before, the system makes a new copy of the contents of HKU\.DEFAULT and stores it in a new subkey whose name matches the user's SID. If the user has logged in before, his subkey under HKU is mapped to HKCU, and the logon process continues. There are some subtleties to this process; for example, if the network's using profiles, the system may have to fetch the user's profile from a server if it's not locally cached.

11.5.1 HKU\.DEFAULT

The settings in this hive are used as defaults for new users when they log in. Section 9.1 in Chapter 9 discusses how you can modify these defaults so that all new users get the defaults you set automatically when their HKU subkeys are created.

11.5.2 HKU\sid

Each user account has a unique SID; this SID is also used to identify that account's settings under HKU. For a detailed description of what keys and values are stored under HKU\sid, see the section Section 11.7 later in this chapter.