Why won't the flash drive boot?

Question

Windows

Hello. I can't reinstall/restore the OS because I can't boot from the flash drive.
Lenovo B50-70 laptop, BIOS version - InsydeH20 Rev. 3.7.
I disable Secure Boot, install Legacy Support and Legacy First.
In the list of devices, the flash drive sees every other time. When I put USB in first place, after a reboot, it does not boot from it.
The image of Windows XP and Windows 10 was recorded through Rufus.
What can be wrong?

Answer 1

Go to Boot menu (F12) on boot.
Lenovo laptops may have a special button to call the Bios Menu, which also has a Boot Menu where you can choose what to boot from

Answer 2

Precisely loaded. flash recorded exactly?
It's just the first time I hear such a program ...
UltraISO - software proven over the years

Answer 3

There was a similar problem with one computer, it did not boot from any external devices (USB, PXE, etc.), except for DVD. Try burning the image to DVD and boot from it.

Answer 4

With Lenovo, I generally very often meet with various problems!
Find the reset button on the laptop, it will be a small hole to poke a needle over there, from there, boot from the flash drive.
ps This mode is somewhat different from the usual entry into recovery mode, and what was not loaded in the usual entry is loaded from here.

Answer 5

1: the charatatime function is declared, we take a pointer to a string as arguments.
3: Declaring a `ptr' pointer (ptr - pointer)
4: Declaring an integer type variable `c'
5: start comment
"Ensures that characters sent to stdout are printed as fast as possible -- disable stdout buffering"
7: disable stdout buffering
8: start loop; the loop is executed until it reaches the end of the line (but I think there will be an overflow here)
9: prints a character from the line
10: end of block

Answer 6

Prints a string to stdout without buffering, as, in fact, it is written in the comment