SSD + HDD System, HDD Has Extra Partitions

[birfincankafein]

I installed Windows 10 Pro x64 on my system after installed new SSD. I made clean installation with erasing both SSD and HDD's partitions. Now my Windows 10 shows 2 OS on boot screen.

When I try to open Second Windows 10 OS laptop crashes and booting again and shows reparing Windows 10 message and after that it says can't repair. After that I press F12 on bios screen for choose my SSD and I see 2 Windows 10 OS on boot screen again.

Why this happens? I know I can solve this problem with managing Windows boot file. But I installed Windows 10 on SSD and moved all user folders and install all apps on HDD. There is no Windows or Windows.old folder on my HDD. Why Windows saw 2 OS on my system?

Here is my partition schema:

 

[Colif]

I don't know how you got two win 10 on it, I can see Win 10 decided to put the efi partition on the hdd instead of your ssd, it does that if you have 2 drives available when it installs. Its not helpful if you decide to replace drive as suddenly win 10 doesn't work.

Start again.

remove hdd from PC and put win 10 on ssd again
once it works and boots by itself, then download http://www.dban.org/ and make a USB
remove ssd from pc and put in hdd
run dban on hdd and wipe it clean
once its blank, plug ssd back in and use disk management to format hdd so you can use as storage

 

[SuperSoph_WD]

Welcome to the TH Community, @birfincankafein!

I'd second @Colif's suggestion! It sounds like you most probably had both your SSD & HDD connected to the motherboard when you were clean installing Windows 10 onto the SSD. Unfortunately, Windows tends to get confused when having more than 1 SATA devices connected at the time of the installation and this is called an OS confusion. The easiest way to fix it, is to start from scratch, only this time make sure you unplug the HDD from the system until Windows is installed onto the SSD. Afterwards, plug back the secondary HDD and re-format it through Disk management.

However, before proceeding with this, make sure you back up all important files somewhere off-site!

I'd also recommend following this detailed step-by-step guide on Windows Install & Optimization for SSDs & HDDs.

Hope it helps you! Best of luck!
SuperSoph_WD