On my PC, encryption option doesn't show up in setting. But I managed to find bitlocker in control panel.
On my try, Bitlocker can encrypt all the drives except drive C.
Drive D (share the same NVMe SSD with drive C), Drive F (2TB HDD), drive G (3 TB HDD), drive H (4TB HDD) it's all fine.
But not with drive C. I don't know what preventing it from applying the encryption.
For more information, I setup Win 11 Pro in offline mode (did not use an MS account). UEFI and Secure Boot enabled and my PC has a TPM 2.0 chip. Not domain joined.
10/1 DSL (the fastest line speed available here...)
Browser
Mozilla FF 91.2.0esr
Antivirus
Defender
Other Info
W10 GUI heavily modified with Stardock Blinds "7 for 10" skin and Startmenu.
No MS Account and no MS apps.
I upgraded to W10 only for gaming purposes, otherwise I'd kept my beloved W7 Ultimate x64
Operating System
W11 Pro
Computer type
PC/Desktop
Manufacturer/Model
custom
CPU
Intel Core i5-2500
Motherboard
Gigabyte PH67A-D3-B3
Memory
4GB
Graphics card(s)
MSI Geforce 1050Ti
Sound Card
onboard
Monitor(s) Displays
FujitsuSiemens 19"
Screen Resolution
1280x1024 (oldschool 4:3)
Hard Drives
Samsung EVO850 SSD 250GB + Samsung 1TB HDD
PSU
be quiet 550W
Case
Mars MCNW ATX Gaming
Cooling
be quiet PURE ROCK SLIM BK008
Mouse
oldschool Dell optical wired
Keyboard
Dell German 102
Internet Speed
slow DSL, 10/1Mbps, but thats the best offer here
Browser
Mozilla 91.2.0esr
Antivirus
Defender
Other Info
This is an older PC for testing new OS,
Furthermore: 4 Dell/HP laptops on Win7 Ultimate x64, used for NAS, Media server, browsing, workshop and sound studio