No bootable to Unallocated Space

[korialz]

So after a brownout (ups didn't have enough power to wait for my pc to shutdown), I couldn't boot anymore. There is a "no bootable device found" thing showing up. I did everything to fix this (reseating satas, etc.) but nothing. I have no choice but I decided to fix or just reinstall my OS. But when I was in the part where I have to choose where to install the OS, I notice my hard drive became Unallocated. Why did this happened?
Acutally there is no important files there and I could just reformat it...

 

[Paperdoc]

The Install process for your OS includes the tools you need. First, when you start up the process and choose the HDD to install onto, look for a tool to Delete any existing Partition. Delete any and all that exist, so the entire HDD truly is Unallocated Space. THEN do the Install. That process automatically does two initial steps for you. First it Creates a Partition where the OS will go (and may create another for system use), then it Formats those Partition(s) so they are ready to use. THEN it actually copies all the files necessary to compete the Install.

 

[korialz]

i think I already messed it up during the process of fixing it.I used my laptop and an external case for it. before it still shows in Disk magement(as unallocated) of my laptop. what I did was, I made a partition of the disk(without formatting or deleting anything). while it was in the process of finalizing the partition the disk management crashed.now everytime I open disk management while the hd is still inserted(externally) , disk management wont stay open and will crash every time. nevertheless, before the disk management crashes I could still see there is a partition made. So I tried installing an os in it but it gets an error minutes after it says "copying files". Forgot what was the error saying.

edit: forgot to mention, there is a Warning Sign/Details in the windows installation. When I click this it will say something like it wont install OS on the drive since it will be dead soon. I guess its already dead huh? or is there something the installation detects on drive thats why its displaying this warning details and it still could be fixed?

 

[Paperdoc]

It certainly is possible that the HDD has serious errors. But it also is possible that it does not, but it DOES have data on it that makes no sense, so Windows Install gives up.

I suggest your best path forward is to get a disk diagnostic utility package and do some cleaning and testing of the HDD. To do this you would need a few things.

1. In preparation, you need the diagnostic package on a self-booting CD. Find out what company made the HDD. Go to their website and look for a free downloadable utility package. For example, if it's made by WD, get their Data Lifeguard package. If it's from Seagate, get their Seatools. In either case, download the "for DOS" version. It is a single .iso file that is a complete image of a bootable CD with all the utilities on it. You need to "burn" that file to a blank new CD using a disk burning utility like Nero that can handle .iso files.
2. Now, you'll need to use a desktop machine for these. Shut it down. Inside, DIS-connect any and all HDD's and SSD's so that only the optical drive unit is connected. Now connect your faulty HDD to power and a SATA port. Place the new diagnostic CD you made in the optical drive. Turn on and go immediately into BIOS Setup. In there go to the Boot Priority sequence and set it to boot from the optical drive first. Save and Exit, and the machine will boot from that CD. It will install a mini-DOS operating system in RAM, and this can run even though there is NO HDD connected that actually works. Then you'll get a menu of tools you can use on the faulty HDD (the only drive in the system right now).
3. You can run the Short Test for flaws in the drive, and maybe the Long Test if it passes Short. If the HDD appears not to have any bad problems, I suggest you then run what is called a Zero Fill on that HDD. This process will completely destroy any data on the HDD, so that is why I said to DIS-connect all other drives to be SURE you don't destroy data on the wrong drive! The Zero Fill will take a long time, so be patient. It will over-write any bad data and cause an internal self-diagnostic and self-fixing process to run. If the disk actually does not have real hardware problems, this will make the disk absolutely clean and free of any errors so Windows will have no problem with it.
4. If all that works and you have a HDD that appears to have no errors, remove the CD from the optical drive and shut the system down. Remove the faulty drive, RE-connect all the normal drives in the machine, and boot immediately back into BIOS Setup. Go to Boot Priority again and set it the way it is needed for normal use, then SAVE and EXIT. It should reboot as it always did.

After that work, you should be able to mount that fixed-up HDD in any machine, place a Windows Install disk in its optical drive, and Install Windows on it normally.