To hide drives

HKEY_LOCALMACHINE\Software\Microsoft\Windows\
CurrentVersion\Policies\Explorer - this changes the settings for all users on the machine.
You may have to create the key folder "Explorer" manually.

3. In the Explorer key folder, create a new DWORD value by right-clicking Explorer, then
choosing New DWORD value. Name the value "NoDrives" (without the quotes). This value defines
local and network drive visibility for each logical drive on the computer. All drives will be
visible as long as this value's data is set to 0.

4. Following the table below, enter the decimal number corresponding to the drive(s) you want
to hide as NoDrives value data. When you right-click on NoDrives and choose Modify, make
sure you select Decimal base, not Hexadecimal.And restart windows

Drive Number to hide
A: 1
B: 2
C: 4
D: 8
E: 16
F: 32
G: 64
H: 128
I: 256
J: 512
K: 1024
L: 2048
M: 4096
N: 8192
O: 16384
P: 32768
Q: 65536
R: 131072
S: 262144
T: 524288
U: 1048576
V: 2097152
W: 4194304
X: 8388608
Y: 16777216
Z: 33554432
All drives 67108863