It's been a while since I haven't posted here, but I managed to work around a hell of a problem, that seems to plague everybody and his cousins, and Google was of no help. Even though it's almost 3am, I think it is worth sharing before I forget everything.
A bit of context: Today is my daughter's birthday, and we have to decided to offer her a computer.
I chose an ASUS notebook with Windows 8. I performed some basic setup (mail, antivirus, removing apps not suitable for children - in my opinion -, and so forth). I did not manage to install the system updates, so I decided to give it a try yesterday evening; it would be a long and tedious process, but I wanted to have the system as up-to-date as possible, perhaps even installing Windows 8.1 (which requires an up-to-date 8 system), before letting my daughter go on the wild west of the internet.
I tried different approaches to install the updates and, during a reboot, Windows decided to install about 60 updates (out of 99). I layed down with a book while waiting for it to proceed.
Coming back a bit later, I had a message telling me that the updates failed, and that the system was reverting changes. OK, it was getting late, so I just thought let it revert it and I'lll check that later.
The revert process ended, the computer rebooted and... I was back to the "Reverting change" message!
I let it run again (about 30 minutes), reboot, and here we go again with reverting changes.
I googled the whole planet Earth, but to no avail. Basically, I discovered I may be able to go back to the previous system state by opening this and that menu in the system. But I cannot boot the system!
Someone said he fixed the problem by pressing all the F8 F9 F10 F11 F12 keys simultaneously at boot time, which I tried, to no avail. All in all, there seems to be a mysterious boot menu somewhere, but I couldn't manage to find of it.
OK. It's 2 in the morning of my daughter's birthday, and her present is AWOL. Talk about pressure at your daily job!
I ended up on a discussion on a shady forum, with content partially deleted, and with the sentence "It's strange F12 doesn't work for you."
I tried using F12 at boot time, an failed. I tinkered with it a bit, and ended up doing this:
1. Switch off the computer
2. Switch it on and go to the BIOS (DEL key on my daughter's ASUS)
3. Do not do any change to the BIOS, and exit without savings.
4. Put your finger on the F12 key and let it there.
And Windows tells me that it failed to start, and proposes me to either reboot or access some mysterious advanced options. These options are a course on what-to-not-do on UI design, since I had to go through 3 or 4 pages before finding the feature letting me restore to a savepoint, located in time before the updates installed by Windows Update, without losing data (but I was proposed to reformat everything on the first page...)
And. It. Worked.
I will fix this Windows update later, but now the computer is its gift wrap, and I'm going to bed, because I feel it will be a long day tomorrow, er, today.