ASRock B550M Pro4 Motherboard BIOS Update Method and Notes

The PC I use is a BTO PC purchased from PC Koubou, and is equipped with an ASRock B550M Pro4 motherboard.

For those of you using an ASRock B550M Pro4 motherboard, are you considering updating your BIOS?

Recently, with the recent trend of strengthening Windows security, it has become recommended to update the Secure Boot Key (2023 KEK/DB/PK), and I updated my BIOS for this purpose. BIOS updates are generally not recommended unless there is a problem with your PC, but this is not the case when there is a special reason for strengthening security, as in this case.

In this article, I will explain in detail the steps I took to update the BIOS on my ASRock B550M Pro4, including common pitfalls and things to be aware of, as well as the license activation issues I encountered and how to resolve them. If you're using the same motherboard, please refer to this article.

Important preparations and precautions before updating the BIOS

Updating the BIOS is a delicate process that affects the very core of your PC. To prevent unexpected problems, be sure to follow the preparations and precautions below.

1. Take a full backup of your PC:To prepare for the worst case scenario, be sure to back up your entire PC in case Windows won't start.

2. Disable BitLocker/Device Encryption:Updating the BIOS may cause your PC to recognize that its hardware configuration has been changed, which can lock out BitLocker and device encryption. Be sure to disable these beforehand.

• Confirmation method: Settings > Privacy and Security > Device Encryption > Device Encryption or BitLocker Drive Encryption

3. Disable AMD fTPM switch:It is recommended to disable the AMD fTPM switch in the BIOS settings before updating the BIOS. This will help prevent unexpected authentication issues during the update.

• procedure: Restart your PC, press F2 to enter BIOS, go to the "Advanced" tab > "CPU Settings" > set "AMD fTPM switch" to "Disabled", save and restart.

4. Ensure a stable power supply:If your PC loses power during a BIOS update, it may damage the motherboard and cause your PC to become unbootable. Make sure your PC's power cord is securely connected to a power outlet, and if possible, use an uninterruptible power supply (UPS) or a power strip that is protected against lightning surges to ensure a stable power supply.

ASRock B550M Pro4 BIOS Update Actual Steps

Step 1: Download the BIOS file

1. Go to the B550M Pro4 product page on the ASRock official website and go to the "Support" tab > "BIOS" section.
   • https://www.asrock.com/mb/AMD/B550M%20Pro4/index.jp.asp#BIOS(Directly open the "BIOS" section)
2. Download the latest version of the BIOS file (in my case, the version released on 10/09/2025, which includes the Secure Boot key update).
   • There are two links, "Global" and "China." Choose "Global." For some reason, I couldn't download the "China" link.
   • "Before updating the BIOS, please read the instructions on the BIOS download page. If the system is already working properly, it is not recommended that users update the BIOS." Click "OK" to start the download.
3. The downloaded zip fileUnzipIn the middle,B550MP43.90” (Note: The file name varies depending on the version).

Step 2: Copy to USB memory and prepare

1. Prepare an empty USB memory stick (about 100MB of free space is fine. It is recommended to format it in FAT32 format).
2. The BIOS file extracted in step 1 (e.g. "B550MP43.90") directly to the root folder (top level) of the USB memory.
   • What is the root folder?: This refers to the location where the files are immediately visible when you open the USB memory. Do not place them inside a folder.
3. Leave the USB memory stick containing the BIOS file inserted into your PC.

Step 3: Disable fTPM (double check)

1. Restart your PC and at startup Press F2 key repeatedlyto enter the BIOS/UEFI setting screen.
2. "アドバンスド" tab.
3. "CPU settings"Choose.
4. "AMD fTPM switch" item to "Disabled(Disabled)".
5. Press F10 to save your settings and restart your PC.

Step 4: Update BIOS with Instant Flash

1. Restart your PC and try again Press F2 key repeatedlyto enter the BIOS/UEFI settings screen.
2. "tool" tab.
3. "instant flash"Choose.
4. When you are asked "Do you want to continue?", select "Yes"Or"Yes"Click.
5. The BIOS file selection screen will appear. Here, select the file you copied to the USB memory (e.g., "B550MP43.90") appears in the list.
6. Select the file in question and click "NEW"Or"FlashClick " to start the BIOS update.
7. Do not turn off the PC, remove the USB memory, or perform any other operations until the update is complete. This is a very delicate task.
8. Once the update is complete, your PC will restart automatically.

Step 5: Initialize BIOS settings and enable Secure Boot

After updating the BIOS, the settings will be initialized, so you will need to make the necessary settings again to start Windows 11.

1. Once your PC has restarted, Press F2 key repeatedlyto enter the BIOS/UEFI settings screen.
2. "Start-upOpen the Boot tab.
3. "CSM (Compatibility Support Module)" item to "Disabled(Disabled)".
   • the reasonTo enable Secure Boot, you must disable CSM.
4. Press F10 to save your settings and restart your PC.
5. again Press F2 key repeatedlyto enter the BIOS/UEFI settings screen.
6. "SecurityOpen the Security tab.
7. "Secure boot(Secure Boot)" item to "Enabled(Enabled)".
8. Underneath it is "Installing the default Secure Boot keysClick "Install Default Secure Boot Keys."
9. When you see "Load Default Secure Variables," clickYes"Or"Yes"Click.
   • the reason: The Secure Boot variables are empty in the BIOS update, so the initial security keys are loaded.
10. Press F10 to save your settings and restart your PC.

Now your BIOS is updated, Secure Boot is enabled, and the keys are installed.

How to check the version and expiration date of Windows Secure Boot certificate

Problems encountered after updating BIOS and solutions

I had the following problem on my PC after updating the BIOS. Please refer to this if you are in the same situation.

Windows license activation is lost

Because updating the BIOS affects the PC's hardware configuration, Windows may recognize the hardware as having been changed and deactivate the license. This actually happened to my PC.

symptom:

• On the Settings > System > Activation page, the message "Windows reported that your device's hardware has changed. Error code: 0xC004F211" is displayed.
• Even after troubleshooting, I still get the message "Windows couldn't activate on this device."

• When I click the link "I recently changed hardware on this device," my PC doesn't appear in the list of available devices.

Solution: Re-enter your product key

1. It is attached to the side or top of the PC or to the box it came in.Windows product keyOnly
2. On the "Settings" > "System" > "License Activation" page,Change product key"Click.
3. Enter the product key you have prepared correctly and click "Next".
4. Your license has now been successfully reactivated.

Summary

Updating the BIOS on the ASRock B550M Pro4 is a very useful task, especially if you have the express purpose of updating the Secure Boot keys.

However, this procedure is delicate, and there is a possibility that unexpected problems such as license deactivation may occur.

Please refer to the steps and precautions in this article to ensure careful preparation and careful work, and to maintain the security and stability of your PC.