Bear

Pretty much as VapechiK says. Here's a how-to list based on your screenshot at the top of this topic:
Create a folder, e.g. called "mounts" or "disks" or whatever, in the root of any physical drive that ISN'T your drivepool and IS going to be always present: You might use your boot drive, e.g. c:\mounts You might use a data drive that's always plugged in, e.g. x:\mounts (where "x" is the letter of that drive) Create empty sub-folders inside the folder you created, one for each drive you plan to "hide" (remove the drive letter of): I suggest a naming scheme that makes it easy to know which sub-folder is related to which drive. You might use the drive's serial number, e.g. c:\mounts\12345 You might have a labeller and put your own labels on the actual drives then use that for the name, e.g. c:\mounts\501 Open up Windows Disk Management and for each of the drives: Remove any existing drive letters and mount paths Add a mount path to the matching empty sub-folder you created above. Reboot the PC (doesn't have to be done straight away but will clear up any old file locks etc). That's it. The drives should now still show up in Everything, as sub-folders within the folder you created, and in a normal file explorer window the sub-folder icons should gain a small curved arrow in the bottom-left corner as if they were shortcuts.
P.S. And speaking of shortcuts I'm now off on a road trip or four, so access is going to be intermittent at best for the next week.

hi
yes, what DaveJ suggested is your best bet.
and Shane is correct (as usual).  you have (in)effectively mounted your pool drives into a folder on the pool and this is causing Everything to fail and WILL cause other problems down the road.  to quote Shane:   "Late edit for future readers: DON'T mount them as folders inside the pool drive itself, nor inside a poolpart folder. That risks a recursive loop, which would be bad."
 
1.  on your C (Bears) drive, recreate the D:\DrivePool folder where you mounted your drives 301 302 etc.  so you now have C:\DrivePool with EMPTY folders for all your drives that are in the pool.  DO NOT try to drag and drop the DrivePool folder on D to C  mmm mmm bad idea.  just do this manually as you did before.
2.  STOP the DrivePool service (win + R, type 'services.msc' find StableBit DrivePool Service and Stop it).
3.  go to Disk Management and as in https://wiki.covecube.com/StableBit_DrivePool_Q4822624   remount all the drives from D:\DrivePool into the drive folders in C:\DrivePool.  windows may/will throw some warnings about the change.  ignore them and remount all 16 from D:\DrivePool to C:\DrivePool. 
4.  reboot
now your file explorer should show Bears C:, DrivePool D:, and maybe G X and Y too, idk...
enable show hidden files and folders and navigate to C:\DrivePool.  doubleclicking any of the drive folders will show the contents of the drive if any and a hidden PoolPart.xxxx folder.  these PoolPart folders are where the 'POOL' lives.  and this is where/how to access your data from 'outside' the pool.  be careful they are not deleted.
5.  go to the folder DrivePool on D and delete it.  totally unnecessary after the remount from D to C and now it is just a distraction.
6.  life is good.
 
some advice:
for simplicity's sake, i would rename C:\DrivePool to C:\Mounts or something similar.  having your pool and the folder where its drives are mounted with both the same name WILL only confuse someone at some point and bad things could happen.
hope this helps
cheers

I duplicate all HDD's, except the ones that have the OS's on them, with those, I use 'minitool partition wizard'.
The 4 bay enclosures I linked to above, I have 2 of the 8 bay ones, with a total of 97.3TB & I now have only 6.34TB free space out of that.  It works out cheaper to get the little 4 bay ones, and they take HDD's up to 18TB - sweet
If you like the black & green, you could always get a pint of XXXX & put green food dye into it, you don't have to wait till St. Patrick's Day.  That would bring back uni days as well     🤣   🍺   👍
" A pirate walks into a bar with a steering wheel down his daks
 He walks up to the bar & orders a drink
 The barman looks over the bar and says, "do you know you have a steering wheel down your daks?"
 The pirate goes, "aye, and it's driving me nuts""   🤣   🤣   🤣
🍺   👍   🍺   cheers
 

I duplicate all HDD's, except the ones that have the OS's on them, with those, I use 'minitool partition wizard'.
The 4 bay enclosures I linked to above, I have 2 of the 8 bay ones, with a total of 97.3TB & I now have only 6.34TB free space out of that.  It works out cheaper to get the little 4 bay ones, and they take HDD's up to 18TB - sweet
If you like the black & green, you could always get a pint of XXXX & put green food dye into it, you don't have to wait till St. Patrick's Day.  That would bring back uni days as well     🤣   🍺   👍
" A pirate walks into a bar with a steering wheel down his daks
 He walks up to the bar & orders a drink
 The barman looks over the bar and says, "do you know you have a steering wheel down your daks?"
 The pirate goes, "aye, and it's driving me nuts""   🤣   🤣   🤣
🍺   👍   🍺   cheers
 

I have a similar setup on my backup NAS. All non-Drivepool drives are mounted to folders at c:\mount and I can access the drives directly from there if needed.

Specifically, StableBit DrivePool and Windows doesn't need letters for the disks, nor even folder mount paths.  These are there to make it easier for users to access the drives.
But as somebody with 20+ drives, mounting the drives to folders makes things very easy.  And we do have a guide on how to do so: 
https://wiki.covecube.com/StableBit_DrivePool_Q4822624

Windows only supports drive letters A through Z.
However, it isn't necessary for a drive (other than the boot, system and pagefile drive, and perhaps CD/DVD drives and similar) to have a letter; drives can instead be accessed by mounting them as folders in another drive (e.g. C:\Array\Drive27, C:\Array\Drive28, etc) and furthermore itself DrivePool can have drives form part of a pool without being lettered or mounted at all.
To add/remove drive letters or mount drives as folders in other drives, use Windows Disk Management: right-click a volume and click Change Drive Letters and Paths...
Late edit for future readers: DON'T mount them as folders inside the pool drive itself, nor inside a poolpart folder. That risks a recursive loop, which would be bad.

To get this started apparently:
 
My server was kind of piecemeal constructed.
 
 
I recently purchased a 42U HP Rack from a local company (via Craigslist), for super cheap ($50, so literally couldn't pass it up)
 
Sophos UTM (Home): 
Case: Antec ISK 110 VESA case,
Mobo (SoC): ASRock RACK J1900D2Y
RAM: 4GB of non-ECC RAM
OS Drive: Samsung 850 Pro 120GB SSD 
 
 
Storage Server:
Case: SuperMicro 847E26-R1K28LPB
OS: Windows Server 2012R2 Essentials
CPU: AMD FX-8120  Intel Xeon E3 1245v3 (link)
MoBo: ASRock 990FX Extreme3  Supermicro MBD-X10SAT-O (link)
RAM: 2x8GB Crucial ECC
GFX: nVidia geForce 9400  Intel HD 4600 (on processor GFX)
PSU: Built in, 2x redundant power supplies (1280W 80+ Gold) 
OS Drive: Crucial MX200 256GB SSD
Storage Pool: 146TB:  4x 4TB (Seagate NAS ST4000VN000) + 8x 4TB (WD40EFRX) + 12x 8TB Seagate Archive (ST8000AS0002), 2x 8TB Seagate  Barracudas (ST8000DM004), 2x 128GB OCZ Vertex 4s
Misc Storage: 500GB, used for temp files (downloads)
HDD Controller card: IBM ServeRAID M1015, cross flashed to "IR Mode" (RAID options, used to pass through disks only), plus an Intel SAS Expander card 
USB: 2TB Seagate Backup Plus for Server Backup (system drive, and system files) using a WD Green EARS 
 
 
NVR (Network Video Record, aka IP camera box) via BlueIris:
Case: Norco ITX-S4 
OS: Windows 10
CPU: Intel Core i3-4130T
MoBo: ASRock Rack E3C226D2I 
RAM: 2x8GB G.Skill 
GFX: ASPEED 2300
PSU: 450W 1U 
OS Drive: 128GB SSD, Crucial M550
Storage Pool: 2x4TB Toshiba HDD
 
HyperV VM Lab:
Case: Supermicro SYS-6016T-NTF (1U case) 
OS: HyperV Server 2012R2
CPU: Intel Xeon 5560  (x2, hyperthreading disabled)
MoBo: Supermicro X8DTU 
RAM: 64GBs (8x8GB) Hynix Registered ECC (DDR3-1333)
GFX: ASPEED 2300
PSU: 560W 1U 
OS Drive: 160GB HDD 
Storage: 500GB Crucial MX200 SSD, using Data Deduplication for VMs
 
 
Emby Server: 
Case: Unknown (1U case) 
OS: Windows 10 Pro x64
CPU: Dual Intel Xeon x5660's (hardware fairy swung by)
MoBo: Supermicro X8DTi 
RAM: 20GB (5x4GB) Samsung Registered ECC
GFX: Matrox (Onboard)
PSU: 560W 1U 
OS Drive: 64GB SSD,
Storage: 128GB  (cache, metadata, transcoding temp) 
 
 
Netgear GS724T Smart Switch
24 port, Gigabit, Managed Switch (one port is burned out already, but it was used). 
 
 
Dell 17" keyboard and monitor tray (used, damaged, propped up). 
 
Images here: http://imgur.com/a/WRhZf
 
 

Here is my network hardware.  Not a great image, but that's the 24 port, managed switch, a punchout block, waaay too long cables, cable modem and Sophos UTM box.
 

Misc drawers and unused spares. 
 

 
And my servers. HyperV system in the 1U, and my storage server in the 4U. And the Cyberpower UPS at the bottom. 
 
What you don't see is the NVR box, as it's been having issues, and I've been troubleshooting those issues.