I believe that I am identifying your Windows drive (/dev/sdb) as a physically separate disk. That is very good, because Windows does not “play nice” with Linux.
I would recommend that only a Linux (oriented/dedicated) disk be the target for your GRUB installation, and that GRUB never finds its way to becoming installed on your “pure” Windows disk drive.
If GRUB is already installed on the Windows drive, I don’t know how to go about “purging” that from your 500GB /dev/sdb drive in a way that the “virgin” Windows MBR partition table structure can be restored. Maybe one of the experts from the Community could guide you in performing that particular “cleanup”.
Beyond that, I would refer you to another posting I made earlier as to how to approach the installation and setup of the GRUB to ensure dual-boot or multi-boot, but still making the Windows boot available upon request from the GRUB boot menu. That is outlined here:
Given your circumstances, assuming your “primary” Linux disk is the 4TB /dev/sdd and the 4TB /dev/sdf is your external USB-attached backup drive, I suggest that you start by
-
unplugging all writeable internal and external drives,
-
only plug in your “primary” Linux drive, 4TB
/dev/sdd,
then proceed as I outlined in the post I mentionned.
IMPORTANT:
The drive letters WILL CHANGE after you change the drive boot priority sequence “shuffle” that you need to do!
Before unplugging anything, I suggest that you perform that shuffle, then re-run the lsblk command to get the updated reference to the drive letters for each of those drives.
My recommendation is that your “logical” boot priority sequence be set to the following:
- (plug-n-play) Hitachi DVDR drive /dev/sr0
- (plug-n-play) External USB stick drive (??? may not be listed if not plugged in)
- 4 TB (internal) current /dev/sdd
- 4 TB (external) current /dev/sdf
- 2 TB (internal) current /dev/sdj
- 250 GB (internal) current /dev/sda
- 500 GB (internal) current /dev/sdb
- 120 GB (internal) current /dev/sdc
- 1 TB (internal) current WDC /dev/sdh
- 1 TB (internal) current TOSHIBA /dev/sdg (??? no partition table ???)
- 128 GB (internal) current Ventoy /dev/sdi
Be sure you understand exactly what you are doing before you actually set about doing it.
If at any point you are uncertain, ask before doing (possibly irreversable damage)!
If you want to “reclaim” the Linux-related space associated with the sdb5, sdb6 and sdb8 partitions for Windows-specific usage, move the contents that you wish to preserve from those to one of the other Linux drives, then
- delete those partitions,
- also delete sdb4 and sdb7, then
- either create a new NTFS partition to encompass all the space freed up by those, or
- grow sdb3 to encompass all that free space.