Qu’est-ce que le BIOS ?

Le BIOS ( Basic Input Output System ) est un petit programme qui s’exécute au démarrage de l’ordinateur et qui permet de configurer les paramètres de base du système, comme l’heure, la date, le mot de passe ou l’ordre de démarrage. Le BIOS est stocké dans une mémoire non volatile (ROM) qui conserve les données même lorsque l’ordinateur est éteint.

Qu’est-ce que le MBR ?

Le MBR (Master Boot Record) est le premier secteur du disque dur qui contient les informations de démarrage du système. Il contient un code d’amorçage qui permet de lancer le chargeur d’amorçage (bootloader) qui va ensuite lancer le système d’exploitation. Le MBR permet également de définir la table des partitions du disque dur, c’est-à-dire la façon dont le disque dur est divisé en plusieurs zones.

Qu’est-ce que la partition EFI ?

La partition EFI ( Extensible Firmware Interface ) est une partition spéciale qui remplace le MBR dans le mode de démarrage UEFI . Elle contient les informations de démarrage du système, comme le chargeur d’amorçage ou les entrées de menu. Elle contient également des fichiers de configuration ou des programmes spécifiques au système. La partition EFI est généralement formatée en FAT32 et a une taille d’environ 100 Mo.

Comment créer un support de démarrage externe ?

Pour créer un support de démarrage externe , vous devez disposer d’une clé USB ou d’un CD-ROM vierge et d’un ordinateur fonctionnel. Vous devez ensuite télécharger l’image ISO du système d’exploitation ou de l’outil de réparation que vous souhaitez utiliser. Vous devez ensuite utiliser un logiciel de gravure ou de création de clé USB bootable pour transférer l’image ISO sur le support externe . Vous devez ensuite insérer le support externe dans votre ordinateur et modifier l’ordre de démarrage dans le BIOS pour que le support externe soit prioritaire sur le disque dur. Vous devez ensuite redémarrer votre ordinateur et suivre les instructions à l’écran pour accéder aux options de réparation de Windows.

Windows

“Checking media presence”: what to do if this message appears when Windows starts?

Francis

“ Checking media presence” is a message that sometimes appears when starting a computer , especially under Windows 10 . It means that the system seeks to detect the presence of bootable media, such as a hard drive , USB key or CD-ROM. If the message is followed by No media present, this indicates that the system could not find valid bootable media and cannot launch Windows .

This problem can have several possible causes, such as hard drive failure, BIOS misconfiguration, operating system corruption, or virus infection. Fortunately, there are solutions to resolve it and regain access to your computer. In this article, we will explain how to do it.

How to solve the problem of checking media presence?

Check hard drive

The first thing to do when you encounter the checking media presence message is to check that your hard drive is properly plugged in and recognized by the BIOS . To do this, you must access the BIOS by pressing the key indicated on the screen when starting the computer (usually F2, F10, F12 or Del ).

Next, you need to look for the section that displays the list of boot devices ( boot order or boot priority ) and check that your hard drive appears in this list.

hard drive may . In this case, you will need to fix your internal hard drive not detected by following the appropriate steps. If your hard drive is recognized , but it does not boot properly, you may need to repair the boot sector or restore the operating system.

Check boot mode

If your hard drive is recognized by the BIOS , you must then check that the boot mode is correctly configured. There are two possible boot modes: UEFI and Legacy .

UEFI is a newer, more secure mode that uses a special partition called EFI to store boot information.

Legacy is an older, more compatible mode that uses the hard drive's boot sector (MBR) to store boot information. The boot mode must match the partitioning type of your hard drive.

If you installed Windows in UEFI mode , you need to configure the BIOS in UEFI mode . If you installed Windows in Legacy mode , you must configure the BIOS in Legacy mode . To change the boot mode, you must access the BIOS and look for the section that allows you to modify this parameter ( boot mode or boot option ). You then need to select the appropriate mode and save the changes.

Check the operating system

If the boot mode is configured correctly , you should then check the status of the operating system . Windows may be damaged or infected with a virus and may not launch properly. To check this, you need to use external bootable media , such as a USB stick or CD-ROM containing Windows or a repair tool.

You then need to insert this media into your computer and change the boot order in the BIOS so that the external media takes priority over the hard drive. You then need to restart your computer and follow the on-screen instructions to access Windows repair options . You can then attempt a system restore to a date before the problem, an automatic repair, or a system reset.

Comparison table of UEFI and Legacy boot modes

Fashion	Benefits	Disadvantages
UEFI	Safer	Less compatible
	Faster	More complex
	More flexible
Legacy	More compatible	Less secure
	Simpler	Slower
		Less flexible

FAQ about checking media presence

What is BIOS?

BIOS ( Basic Input Output System ) is a small program that runs when the computer starts and allows you to configure basic system parameters, such as time, date, password or order starting. The BIOS is stored in non-volatile memory (ROM) which retains data even when the computer is turned off.

What is MBR?

The MBR (Master Boot Record) is the first sector of the hard drive that contains the system boot information. It contains boot code which launches the bootloader which will then launch the operating system. The MBR also allows you to define the hard disk partition table, that is, how the hard disk is divided into several areas.

What is EFI partition?

The Extensible Firmware Interface ) partition is a special partition that replaces the MBR in UEFI boot mode . It contains system startup information, such as the bootloader or menu entries. It also contains system-specific configuration files or programs. The EFI partition is usually formatted as FAT32 and is approximately 100MB in size.

How to create external bootable media?

To create external bootable media , you need to have a blank USB drive or CD-ROM and a working computer. You then need to download the ISO image of the operating system or repair tool you want to use. You must then use burning or bootable USB key creation software to transfer the ISO image to the external media . You then need to insert the external media into your computer and change the boot order in the BIOS so that the external media takes priority over the hard drive. Windows repair options .

Conclusion

The checking media presence message may be a sign of a serious problem that is preventing your computer from starting properly . It can have several possible causes like hard drive failure, BIOS misconfiguration, operating system corruption or virus infection. To resolve it, you need to verify that your hard drive is properly plugged in and recognized by the BIOS, that the boot mode is configured correctly, and that the operating system is intact. If not, you should use external bootable media to attempt a Windows . Another possible solution is to disable startup programs that could interfere with the boot process. We hope this article was helpful and you were able to regain access to your computer . If you have any questions or comments, please feel free to leave them below. Thanks for reading us!