Boot.ini
NTLDR's first action is to read the Boot.ini file. NTLDR allows the user to choose which operating system to boot from at the menu. For NT and NT-based operating systems, it also allows the user to pass preconfigured options to the kernel. The menu options are stored in boot.ini, which itself is located in the root of the same disk as NTLDR. Though NTLDR can boot DOS and non-NT versions of Windows, boot.ini cannot configure their boot options.
For NT-based OSs, the location of the operating system is written as an Advanced RISC Computing (ARC) path.
boot.ini is protected from user configuration by having the following file attributes: system, hidden, read-only. To manually edit it, one would first have to remove these attributes. A more secure fashion to edit the file is to use the bootcfg command from a console. bootcfg will also relock the file (setting the file back to system, hidden, and read-only). Additionally, the file can be edited within Windows using a text editor if the folder view option "Show hidden files and folders" is selected, the folder view option "Hide protected operating system files" is unchecked, and the "Read-only" option is unchecked under file properties.
bootsect.dos is the boot sector loaded by NTLDR to load DOS, or if there is no file specified when loading a non NT-based OS.
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