Windows 10: Hard drives cannot be accessed after switch from Win7 to Win10

Hello. I am a victim of an apparently rare bug.


I wanted to try out Win10 as a partition for a dual boot option (Since some games run better on Win10 than Win7).


I heard rumors of Win10 being incredibly agressive but I had no idea how much. Win10 tried to eat and destroy my Win7 partition by messing with, I'm not sure, system files ? Apparently everyone on the web are saying that it's impossible to have a dual boot of Win7 and Win10 because Win10.


Then I realized that out of 2 SSDs and 3 hard drive, 1SSD and 2 hard drive could not be accessed anymore. No matter what. I tried to boot with win10, I tried to boot with Win7, it didn't work.


I bought an USB > SATA adapter to try and see if it would work that way, it doesn't.


This is what Disk Management shows me for one of my hard drive when linked through the USB > SATA adapter.





At first I thought it could have been a virus, one of those locking trojan that makes you pay to unlock your hard drive, but it really doesn't look like it. No prompt, no infection, Malware Bytes, Rogue Killer, Avast... No information whatsoever.


What is going on ?


I have several friends that have had troubles with Win10 and had to go back to Win7 because of a lot of problem with programs, drivers for hardware, but I never heard of problems for hard drives.


I have now deleted the Win10 partition but am left with 3 crippled drives.


Can someone please help me ?


Thank you.

:)

 

Sharing drives with Win7 & Win10

My system is running both Win7 & Win10 on different SSD. There are 2 more HDDs of 2TB each in the PC. After using them in Win10 & then switch back to Win7 the 2HDDs will be scanned at bootup over & over again. Those data created in Win10 are not accessible
in Win7.

Then I got an USB flashdrive 64Gb created in Win7 & then used in Win10. After that it can't be accessed in Win7 anymore. Message say to format the drive before usage

 

Sharing drives with Win7 & Win10

There's nothing wrong with the hard disks. If I use them with Win7 alone there's no boot scanning. The moment I share with Win10 & switch back to Win7 then the disks have to be scanned. I ever tried to skip the scan but after bootup the disks are not accessible
in Win7. Those USB flashdrive that I created in Win7 & then used in Win10 which I transferred more data inside is not accessible in Win7 again. It say to format the flashdrive

 

Sharing drives with Win7 & Win10

I uncheck the Fast Startup. Then I shutdown the system & connect an empty hard disk & start up again. Then I format the disk & transferred a few Gb of data to the new hard disk & shut down. After that I swap over to Win7 & startup. Now I can access everything
in the hard disk. Then I transferred 50Gb of pictures & videos to this disk & shutdown. I switch over to Win10 & I could only see the previous data created in Win10 but not the 50Gb of pictures & video from Win7. Back to square one.

In Win7 the new hard disk register at 20% usage but in Win10 it's only 2%

There's something different between Win10 & the rest of the older OS

Then I did a restart & this time there's a boot scanning of the new hard disk. After that I can access all the new data from Win7 & can play all the videos too. I shutdown & switch to Win7 & there's a boot scanning again. Now able to access everything. Why
do the hard disk need to scan at bootup in order to be accessed?

If I share my 2pcs of 2TB hard disks with Win10 a lot of time will be spent on boot scanning. Is there any way to go around this? Until then Win7 is still my primary working system