CSM boot is enabled issue

[godspunisher]

Hello to everyone. A couple of hours ago, I have been attempting to utilize a bootable windows 7 usb drive. However, my laptop has Windows 8 installed. I have gone to the BIOS and not knowing that secure boot was to also be disabled, I just changed from UEFI to CSM boot. Now, I am trying to revert back to UEFI boot, but keys ESC, F1, F2, F3, F4, F5, F6, F7, F8, F9, F10, F11, F12, end, and del, do nothing to access the BIOS again! Also, I tried to run a bootable W8 flash drive to access the advance menu, but it was a fail. Yet, I tried to do a "Reset my PC" with keeping my files, but it keeps saying that the drive is locked. I am going nuts trying to revert back to normal! Any help would be appreciated, please!

 

[Andrei N]

So you tried to downgrade from Win 8 to Win 7 on a UEFI laptop. That was for starters a bad idea.
Now Windows 8 and onward uses GPT as partitioning table for the HDD while Windows 7 uses MBR. This means that in order to switch the OS you need to fully delete all HDD partitions and replace the partitioning table.
Now onto your problem, you failed to write the Laptop make/model in your question. This is important in finding out possible uefi issues and at least the BIOS key.
Also, did you format your C drive, or is it still intact ?

 

[godspunisher]

So you tried to downgrade from Win 8 to Win 7 on a UEFI laptop. That was for starters a bad idea.
Now Windows 8 and onward uses GPT as partitioning table for the HDD while Windows 7 uses MBR. This means that in order to switch the OS you need to fully delete all HDD partitions and replace the partitioning table.
Now onto your problem, you failed to write the Laptop make/model in your question. This is important in finding out possible uefi issues and at least the BIOS key.
Also, did you format your C drive, or is it still intact ?

Good morning Andrei,

Thanks for your reply. Yes, I tried to. However, I am not really W8 inclined. It's for a Toshiba P855-S5312. After choosing CSM Boot, it keeps displaying PXE-M0F or insert bootable media or DVD. Yet, I have not wiped the drive. I am just trying to revert back to UEFI boot with the same hard drive without any type of modification of it.

 

[Andrei N]

PXE-M0F is network boot I think. You need to reset your BIOS to default settings.
Do not attempt to downgrade your OS. You'll lose all your data because of the difference in partitioning tables and you might not get it to work at all.
BIOS keys for Toshiba are F1 and F2. Power off the machine and then power it on. While the screen is still black tap both the keys in quick succession until you get into bios. The last tab should have a default reset key. Set the bios to default, save and exit. Now it should work.

 

[godspunisher]

Andrei,

So, hit both F1 and F2 at the same time?

 

[Andrei N]

one after the other in quick succession.

 

[godspunisher]

Andrei,

I will try in my lunch hour. Also, prior to being on here, I was researching and some forums say that the secure boot was to be disabled. However, I just changed the mode to CSM and did not touch the secure boot. Would this be an issue too?

 

[godspunisher]

So you tried to downgrade from Win 8 to Win 7 on a UEFI laptop. That was for starters a bad idea.
Now Windows 8 and onward uses GPT as partitioning table for the HDD while Windows 7 uses MBR. This means that in order to switch the OS you need to fully delete all HDD partitions and replace the partitioning table.
Now onto your problem, you failed to write the Laptop make/model in your question. This is important in finding out possible uefi issues and at least the BIOS key.
Also, did you format your C drive, or is it still intact ?

one after the other in quick succession.

Andrei good evening,

Unfortunately, F1 or F2 did not work. I tried to do as described with the hard drive out, but it just kept saying to insert a bootable media... This is a dumb thing on my part and frustrating why it won't access the BIOS. Any other steps would greatly appreciated it.

 

[godspunisher]

one after the other in quick succession.

Andrei,

Ok, good news, after messing around with the keys, F12 was the key to access the BIOS again in CSM boot. However, it must be held. Two things are never the same. It might work or not. So, you will need to power down the laptop, hold the F12 key, power on the laptop, and wait till you see the advance boot options. I reset everything to default settings to make sure and manually reverted back to the UEFI boot. In any case, thanks for your help Andrei and hope this helps out anyone with the same issue.

 

[Andrei N]

Sorry for the late reply. Does it work now ?

 

[godspunisher]

Sorry for the late reply. Does it work now ?

Good morning Andrei,
Yes, it worked and back to normal. Thanks again.