The Windows Recovery Boot Menu (WRBM) allows you to restore an image file without using external rescue media. It allows you to boot into the rescue environment using files already located on your C partition. These files load directly into RAM, so it is possible to restore an image of the C partition you booted rescue from. That being said, you should make sure you have created and tested alternate rescue media. Think of WRBM as a convenience and not one you would rely on to consistently restore an image. The reason is that the files you need may not be available on your computer for a number of reasons. External rescue media can be used as your only rescue media (or a backup to the recovery boot menu option) because it does not depend on any recovery files being on your computer.
The Windows Rescue Boot Menu can be rebuilt automatically whenever you rebuild rescue media for any target device. The rebuild process involves updating the stored build files and the boot menu option boots from those files. Windows Rescue Boot Menu is not a replacement for external rescue media. WRBM requires certain files on your HD to be intact, which they may not be in some failures.
2. Yes although the default time is selectable as well as other options. After creating the WRBM and rebooting, an option screen will appear where you can select to boot into WRBM or Windows as well as changing the default time.
3. When a new version is available, selecting "Create Rescue Media" will allow yo to update the boot menu as the option will be offered to you.
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