Data lost due to installation of Win10 over previously installed win10 via boot menu

[Windows Central Question]

Hello everyone!

My Dell Inspiron laptop was running windows 10 and I did another USB installation of windows 10 over it via Boot Menu(where we press F12 after powering up). After complete installation the windows, I could see all my previous files (Desktop files, Documents etc.) but I was unable to OPEN them or COPY them to another location. After a few days, my C drive has shrunk down in size. It was originally 50GB but now it shows as 20GB. 30GB is lost somehow. It doesn't showup as unallocated space in 'Disk Management' either.

My valuable pictures and videos are lost in the process. Is there any way to recover them?

I hope my question is clear. If further clarification is needed, please ask and I would explain it. ANY HELP would be much appreciated!

 

[midnightfrolic]

At this point, your only option would be data recovery. prepare to spend a small fortune. Try this before using the computer any further. Turn it off and stop using it. As using it may overwrite the sectors where data used to be, making it more difficult to recover.

Edit: search around your city for data recovery shop.