I've known my way around Windows for about two decades now, and usually take care of such problems myself. I am familiar with the Disk Management tool, where the partition shows up as healthy and primary. Of course I am thankful that the hard drive works, and the quickest way would usually be to backup, format, and copy back. However, we're talking about 9TB of data here. I'm sure anyone can understand why I would love to skip the format this time around...
As for the back story of this hard drive: I just did a complete overhaul of my primary NAS / home server, which included a motherboard upgrade and a switch from Proxmox Virtual Environment to Windows Server 2022 (you have every right to berate me for that). I don't believe it is a problem specific to the Windows 11 architecture, upon which Server 2022 was built, because another disk I used with Proxmox shows up correctly. Both are formatted in NTFS, but I'm afraid the affected disk was formatted within the Linux architecture, and there might be where things got messy. I had the foresight to format each HDD in NTFS, just in case I would grow tired of Linux and switch back to Windows one day. At least with the other disk, I went the extra mile and formatted it within Windows. I'm afraid I didn't think of that for the affected disk.
The disk does show up in Disk Management with a healthy and primary partition. However, it shows 100% free space, and no drive letter. From the Windows Pre-Installation Environment, the disk shows up with the correct amount of free storage space. When selecting it, it says Windows can't be installed on it, and at the next step I get the error "The partition is of an unrecognized type", as can be observed on the screenshots below:

As for the back story of this hard drive: I just did a complete overhaul of my primary NAS / home server, which included a motherboard upgrade and a switch from Proxmox Virtual Environment to Windows Server 2022 (you have every right to berate me for that). I don't believe it is a problem specific to the Windows 11 architecture, upon which Server 2022 was built, because another disk I used with Proxmox shows up correctly. Both are formatted in NTFS, but I'm afraid the affected disk was formatted within the Linux architecture, and there might be where things got messy. I had the foresight to format each HDD in NTFS, just in case I would grow tired of Linux and switch back to Windows one day. At least with the other disk, I went the extra mile and formatted it within Windows. I'm afraid I didn't think of that for the affected disk.
The disk does show up in Disk Management with a healthy and primary partition. However, it shows 100% free space, and no drive letter. From the Windows Pre-Installation Environment, the disk shows up with the correct amount of free storage space. When selecting it, it says Windows can't be installed on it, and at the next step I get the error "The partition is of an unrecognized type", as can be observed on the screenshots below:

