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LoadOptionAttributes is a [Flags] enum stored in each Boot####, Driver####, or SysPrep#### NVRAM variable. It controls how the UEFI boot manager handles the load option — whether it is automatically processed, visible in the boot selection menu, and how it is categorised. The underlying type is uint, directly matching the 32-bit Attributes field defined by the UEFI specification.

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Namespace

Unified.Firmware.BootService.LoadOption

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Members

MemberValueDescription
ACTIVE0x00000001The boot manager will automatically attempt to boot this entry during the standard boot sequence. Entries without this flag are stored but skipped during auto-boot.
FORCE_RECONNECT0x00000002Applies to Driver#### entries only. After the last Driver#### option is processed, all UEFI drivers are disconnected and reconnected, allowing newly loaded drivers to bind to previously enumerated devices.
HIDDEN0x00000008The entry does not appear in any boot selection menu presented by the boot manager. The entry can still be activated programmatically or via direct selection.
CATEGORY0x00001F00A sub-field mask covering bits [12:8]. Use this mask to isolate or clear the category bits from a raw Attributes value, then compare against CATEGORY_BOOT or CATEGORY_APP.
CATEGORY_BOOT0x00000000The entry is part of normal boot processing. This is the default category and has a numeric value of zero — no category bit is set.
CATEGORY_APP0x00000100The entry is an application that is not part of the normal boot sequence. It can optionally appear in the boot menu or be triggered via a configured Hot Key.

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Common Usage

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Normal Bootable Entry

An active entry that participates in the standard boot sequence and appears in the boot menu. CATEGORY_BOOT is zero, so specifying it explicitly or omitting it produces the same result. 
LoadOptionAttributes attrs = LoadOptionAttributes.ACTIVE;

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Hidden Entry

An active entry that is excluded from the boot selection menu. Useful for maintenance or recovery entries that should only be invoked programmatically. 
LoadOptionAttributes attrs =
    LoadOptionAttributes.ACTIVE |
    LoadOptionAttributes.HIDDEN;

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Application Entry

An EFI application that is not part of the normal boot sequence. It may be shown in a boot menu or triggered by a Hot Key if the firmware supports it. 
LoadOptionAttributes attrs =
    LoadOptionAttributes.ACTIVE |
    LoadOptionAttributes.CATEGORY_APP;

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Inspecting the Category of an Existing Entry

Use the CATEGORY mask to isolate the category bits from a raw attributes value before comparing: 
LoadOptionAttributes rawAttrs = existingEntry.Attributes;
LoadOptionAttributes category = rawAttrs & LoadOptionAttributes.CATEGORY;

if (category == LoadOptionAttributes.CATEGORY_APP)
{
    Console.WriteLine("This is an application entry.");
}
CATEGORY_BOOT has the value 0x00000000, meaning it is the default state when no category bits are set — not an independently toggled bit. Do not use HasFlag(LoadOptionAttributes.CATEGORY_BOOT) to test for boot category entries; instead, mask with CATEGORY and compare the result to CATEGORY_BOOT as shown above.

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