This section provides an overview of just that section of the registry which applies to the file associations and Windows Explorer context sensitive menus.
The registry is divided into sections called Hives. (Perhaps this reflects the idea that Microsoft is the master (queen bee) and that all other applications are drones (slaves). Or perhaps it is simply that the registry is honeycombed with data.)
Physically, most of the Windows 95 registry is stored in 2 files - user.dat & system.dat. In theory,
On Windows NT 4.0 (and above), a different file structure is used. There appear to be 2 Default files. It is not clear how these are related.
Key | File | NT 4 Size | XP Size |
---|---|---|---|
HKEY_CURRENT_USER (alias for) HKEY_USERS\{User SID} | c:\winnt\profiles\{userID}\Ntuser.dat | 444 KB | 3,328 KB |
HKEY_USERS\.DEFAULT | c:\winnt\profiles\Default User\Ntuser.dat | 200 KB | 232 KB |
HKEY_USERS\.DEFAULT | c:\winnt\system32\config\default c:\winnt\system32\config\default.LOG | 136 KB 1 KB | 512 KB 1 KB |
HKEY_LOCAL_MACHINE\SOFTWARE | c:\winnt\system32\config\software c:\winnt\system32\config\software.LOG | 2,396 KB 1 KB | 12,800 KB 1 KB |
HKEY_LOCAL_MACHINE\SYSTEM | c:\winnt\system32\config\system c:\winnt\system32\config\system.alt | 1,580 KB 1,580 KB | 4,352 KB n/a |
HKEY_LOCAL_MACHINE\SECURITY | c:\winnt\system32\config\security c:\winnt\system32\config\security.log | 32 KB 1 KB | 256 KB 1 KB |
HKEY_LOCAL_MACHINE\SAM | c:\winnt\system32\config\sam c:\winnt\system32\config\sam.log | 24 KB 4 KB | 256 KB 1 KB |
On a NT 4 Service Pack 4 system (Nov 2000), the software key (hive/file) was 9,580 Kb, the exported text file was 6,429 Kb. No wonder the system gets slower as you use it. (Compare this value to that for a new machine in the table above - 2,396 KB.)
Watch it, XP is a pig. The software hive grew from 2 meg (Win NT 4) to 13 Meg. Note also that the user profiles have moved from the windows directory to
C:\Documents and Settings\{userID}\Ntuser.dat C:\Documents and Settings\Default User\Ntuser.dat
Is hive the file or the registry key - NT 4.0 help says that it is a file