[SOLVED] USB Bootable Device (Windows 10 Installation) isn't recognized by the BIOS

[Alberto Bj]

Hello, I just want to ask a question.


So I tried to reformat my friends laptop, the BIOS mode is set to UEFI. The thing is, the laptop doesn't recognize the USB Bootable Device (Windows 10 Installer) from the boot menu.
Although I re-arranged the boot order, the laptop just goes straight into the Primary HDD. The order is 3 USB Ports, then the HDD. The laptop ignores the first 3 USB options and goes straight into windows (HDD)

So I fixed this problem by changing the BIOS mode from "UEFI" to "LEGACY" and finally, the laptop recognized my USB Bootable Device (Windows 10 Installer) and I am now ready to reformat.


My Question is: How can I reformat something without changing the BIOS mode from UEFI to Legacy? I know that Legacy mode is the default from old systems before but I saw that the BIOS mode in which the previous OS was installed was in "UEFI". So I am assuming that whoever installed the previous OS in the laptop booted it using UEFI and not having to change it from UEFI to Legacy. So then, how do I create a bootable drive that can be used in both UEFI and Legacy BIOSes?



If there is not, and so if everytime I want to reformat something must always be in "Legacy" Then my Second Question will be: How can I change the boot mode back to UEFI from Legacy after installing the new OS which is (Windows 10).

 

[TerryLaze]

Popular usb tools like rufus will give you the option to use legacy or UEFI so you should create a USB in UEFI mode to avoid all further problems.

As far as I know you can not make one device boot up in both ways it has to be one or the other since this info is stored in the first sector of the device.

It doesn't hurt anything if you leave it in legacy,the main difference is that uefi can see more active partitions if you want to fill up a single drive with lots of OSs,for a normal laptop it doesn't matter.

 

[Alberto Bj]

Popular usb tools like rufus will give you the option to use legacy or UEFI so you should create a USB in UEFI mode to avoid all further problems.

As far as I know you can not make one device boot up in both ways it has to be one or the other since this info is stored in the first sector of the device.

It doesn't hurt anything if you leave it in legacy,the main difference is that uefi can see more active partitions if you want to fill up a single drive with lots of OSs,for a normal laptop it doesn't matter.

Thank you for your answer.


Another follow up question:
I have 3 Storage Devices, 1 SSD for OS and 2 HDD's for storage

If I wanted to make my primary storage (Windows 10 SSD) from MBR to GPT and my BIOS mode from Legacy to UEFI will that mean that I will have to reformat and or clean the whole SSD if Im not correct.

If that is the case, If I change my BIOS mode from Legacy to UEFI and make the SSD a GPT, will my BIOS read the other 2 HDD's or would the BIOS not read them at all because they were previously from Legacy and MBR and I would also have to reformat and clean the other 2 remaining HDD's to convert them to GPT.

 

[TerryLaze]

Thank you for your answer.


Another follow up question:
I have 3 Storage Devices, 1 SSD for OS and 2 HDD's for storage

If I wanted to make my primary storage (Windows 10 SSD) from MBR to GPT and my BIOS mode from Legacy to UEFI will that mean that I will have to reformat and or clean the whole SSD if Im not correct.

If that is the case, If I change my BIOS mode from Legacy to UEFI and make the SSD a GPT, will my BIOS read the other 2 HDD's or would the BIOS not read them at all because they were previously from Legacy and MBR and I would also have to reformat and clean the other 2 remaining HDD's to convert them to GPT.

Normally yes,you should re install windows from the beginning but there are tutorials out there that claim that you can change to GTP without losing your data,I never did it but you can try if you want to.
Only the boot drive(s) are affected any other disk will show up normally.

 

[Alberto Bj]

So having a GPT drive and both an MBR drive could work and work together regardless of the BIOS mode?

 

[TerryLaze]

So having a GPT drive and both an MBR drive could work and work together regardless of the BIOS mode?

BIOS mode is only important for booting, "storage" disks can be whatever.