This timeline shows Windows XP's Setup activity during an unattended installation, to clear up the confusion of when tasks are run.

Configure BIOS to set CD-ROM as First Boot Device. Boot from CD...

1. Loads Drivers
2. Copies files required for Setup to the Hard Disk
3. Copies the contents of your $OEM$ folders to the Hard Disk
4. Reboots the PC...

1. DetachedProgram executes from winnt.sif at T-39 stage
2. Installs Devices
3. Installs Network
4. Installs Start Menu Items
5. Registers Components
6. svcpack.inf executes at T-13 minute stage
7. cmdlines.txt executes at T-12 minute stage
8. SetupParams executes from winnt.sif at T-9 minute stage
9. Saves Settings
10. Deletes temporary files then reboots...

1. Windows logs you in and loads personal settings
2. Both GUIRunOnce from winnt.sif and RunOnceEX executes at the same time
3. Desktop and Taskbar loads

I hope this helps! Please consult the ref.chm file if you ever need to take advantage of DetachedProgram or [SetupParams].

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