My attempts to boot up Windows to flash the BIOS completely failed. So, I sent my laptop to the Ideapad service center with a letter that contained a link to this thread and explained everything I tried to fix it.
I got a short letter back with my laptop saying that they simply flashed the BIOS for me. This seems to have solved the problem indeed; the delete key is working again. I only wish there was a way to flash a rom from the BIOS configuration settings (I heard that some Asus laptops do this) so that I would not dependent on Windows. But in the end, I am really happy with the way this problem has been resolved.
TL;DR: problem is likely a BIOS software problem. BIOS update solves it.
My attempts to boot up Windows to flash the BIOS completely failed. So, I sent my laptop to the Ideapad service center with a letter that contained a link to this thread and explained everything I tried to fix it.
I got a short letter back with my laptop saying that they simply flashed the BIOS for me. This seems to have solved the problem indeed; the delete key is working again. I only wish there was a way to flash a rom from the BIOS configuration settings (I heard that some Asus laptops do this) so that I would not dependent on Windows. But in the end, I am really happy with the way this problem has been resolved.
TL;DR: problem is likely a BIOS software problem. BIOS update solves it.