Why is Windows reporting an empty NTFS partition, when files are written/viewable by Linux? - (happened with exFAT too !!!)

Question

Ubuntu 18.04 LTS; Windows 10; Lenovo Ideapad i7. The exfat and NTFS drivers are at highest available upgrade (Ubuntu).

Photorec and testdisk are being ran in Linux.

Please note that this particular post is about the NTFS aspect of the problem. The next paragraphs is related background information.

Background: I created an exFAT partition in Windows. I used PhotoRec from Linux to recover 400GB of documents from a ddrescue copy of a failing hard drive - written to that exFAT partition. Windows then reported the partition was EMPTY. I went back and forth a few times between OS's, and then the files were also gone from Linux's point of view, but I never modified the partition in Windows. I posted that problem here, along with screen caps showing the related exfat problem: https://askubuntu.com/questions/1200196/files-directories-on-exfat-are-not-visible-from-windows

The problem
I gave up on exFAT, and formatted the partition as NTFS. (Note: Windows Fast-Boot, Secure-Boot, and hibernation were all disabled before the NTFS partition was created.) I re-ran PhotoRec. Yet again, unbelievably, Windows is reporting the partition is EMPTY. I'm not going to go back and forth again between OS's, as that run of PhotoRec takes several hours. I'm going to wait for an answer.

Here are some screencaps and terminal output.

Here's what Windows sees.

Here is the output from GParted (Linux)

Here is the output of some commands in Linux, showing the directories and sizes. No errors were reported mounting the NTFS partition.

me@PC:~$ sudo mount /dev/sda4 /media/me/intNTFS
[sudo] password for me:         
me@PC:~$ lsblk
NAME   MAJ:MIN RM   SIZE RO TYPE MOUNTPOINT
sda      8:0    0 931.5G  0 disk 
├─sda1   8:1    0   260M  0 part 
├─sda2   8:2    0    16M  0 part 
├─sda3   8:3    0 246.7G  0 part 
├─sda4   8:4    0 683.6G  0 part /media/me/intNTFS
└─sda5   8:5    0 998.5M  0 part 
sdb      8:16   0 465.8G  0 disk 
├─sdb1   8:17   0   512M  0 part /boot/efi
└─sdb2   8:18   0  83.7G  0 part /
sdc      8:32   1   7.4G  0 disk 
└─sdc1   8:33   1   7.4G  0 part 
me@PC:~$ 
me@PC:~$ df -hT
Filesystem     Type      Size  Used Avail Use% Mounted on
udev           devtmpfs  3.9G     0  3.9G   0% /dev
tmpfs          tmpfs     789M  1.5M  787M   1% /run
/dev/sdb2      ext4       82G   12G   66G  16% /
tmpfs          tmpfs     3.9G  237M  3.7G   7% /dev/shm
tmpfs          tmpfs     5.0M  4.0K  5.0M   1% /run/lock
tmpfs          tmpfs     3.9G     0  3.9G   0% /sys/fs/cgroup
tmpfs          tmpfs     3.9G   12K  3.9G   1% /tmp
/dev/sdb1      vfat      511M  6.1M  505M   2% /boot/efi
tmpfs          tmpfs     789M   24K  789M   1% /run/user/1000
/dev/sda4      fuseblk   684G  422G  263G  62% /media/me/intNTFS
me@PC:~$ 

Here is a screencap of a partial directory listing of one of the recup_dir directories ( ls -la /media/me/intNTFS/recup_dir.1 )

Why are the files invisible in Windows? It's happening whether I format the partition as exFAT or NTFS.

SUMMARY: Prepare Windows for dual-system with Linux - disable all of fast-boot, secure-boot, and hibernation. Create NTFS partition in Windows (brand new partition). Reboot into Linux. Run PhotoRec. Reboot into Windows. The partition is reported to be empty. Reboot in Linux. The 400GB+ of files are still there. (Also, I tried using exFAT before trying NTFS, as described above.)

UPDATE

After a few reboots, Linux is now also showing the partition is empty. The same thing happened when the partition was exFAT, as described above. I never ran chkdsk in Windows, or did anything with the other drive other tnan opening diskmgmt.msc, and doing a screencap.

Here is what GParted shows now (sometimes the internal drive is set to sda, and sometimes sdb. Linux is on an external 500GB SSD (USB).

Here is the information window on the partition (GParted).

Testdisk doesn't find a partition. (sudo testdisk /dev/sdb4 -> EFI GPT -> Analyze)

I'm going to run a full partition search in testdisk. This will probably take a couple hours. After that I'm going to run chkdsk /f in Windows, to see if it will recover something on a partition that diskmgmt.msc was showing to be empty. I'm not optimistic. (Update, the partition was found,doing a search on sda rather than just sda4, but the partition is empty. The testdisk/photorec forum says to run photorec is this case. I'm not running recovery on a recovery. I can just run photorec again.)

And again, during this whole process fast-boot, secure-boot, and hibernation have all been disabled in Windows this whole time. It looks like I will be running photorec again for a few hours. I wish I had an external 1TB disk to use. (I can use an exFAT partition on the external SSD in Windows.) Note that I can't use FAT32, as PhotoRec is creating files well over 4GB during the recovery process.