Cannot Install Windows 11 on HP EliteBook 850 G8 – SSD Not Detected / Wrong Size Without Intel RST V

[ayseld]

Hello,

I have an HP EliteBook 850 G8 Notebook PC (Intel 11th Gen i7, 16 GB RAM, 512 GB SSD, BIOS T76 Ver. 01.21.00). My laptop no longer boots into Windows – it goes straight into Automatic Repair or sometimes shows recovery errors (0xc0000001).

What I have tried so far

• Created multiple Windows 11 installation USB sticks using the Microsoft Media Creation Tool and Rufus.

• Disabled Secure Boot in BIOS so I could boot from the USB stick. After that, I am often prompted for my BitLocker recovery key, but even when I enter the correct 48-digit key, nothing happens (the system just loops back).

• Changed boot order correctly; USB stick boots fine.

• Ran HP hardware diagnostics: the SSD passes all tests.

• In BIOS, the SSD is detected.

• In Windows Setup, the SSD either does not show up, or shows incorrectly as 2 TB Unallocated (instead of 512 GB).

• I learned that my model uses Intel VMD (Volume Management Device) for storage.

• Downloaded the official Intel Rapid Storage Technology (RST) driver from HP (sp145779.exe).

• Extracted the driver (iaStorVD.inf, iaStorVD.sys, etc.).

• Copied the VMD\x64 driver folder to a FAT32 USB stick.

• In Windows Setup, I load the driver → two options are shown:

  • Intel RST VMD Controller 9A0B

  • Intel RST VMD Managed Controller 09AB

• No matter if I select only 9A0B or both drivers, Setup always ends in a Blue Screen (Stop Code: DRIVER_PNP_WATCHDOG).

• I also tried disabling VMD in BIOS, but then the SSD is shown incorrectly as 2 TB Unallocated.

• I performed a BIOS factory reset, but the issue remains.

• I also physically removed and reinserted the SSD to make sure it was seated properly – no change.

My questions

1. In BIOS, under Advanced → System Options, should Configure Storage Controller for VMD be enabled when installing Windows 11?

2. Is it normal that the SSD shows as “2 TB Unallocated” instead of 512 GB when VMD is disabled?

3. If VMD must stay enabled, how can I avoid the DRIVER_PNP_WATCHDOG crash during installation?

4. Is there a recommended step-by-step guide from HP for reinstalling Windows 11 on this model when VMD is enabled?

I just want to reinstall Windows 11 and recover my system, but I cannot get the installer to recognize the SSD properly even with the RST drivers loaded.

Any help would be greatly appreciated

[tk_srq]

@ayseld,

If you see 9A0B and 09AB displayed with iaStorVD.inf driver, the Windows installer should've loaded the driver to detect and display the storage drive, as that is the right driver file your Intel i7 11th gen processor needed (VMD needs to be enabled in the BIOS). 

The issue of the .inf driver not being loaded may have something to do with the way your Windows installation usb drive was created or the usb drive itself. 

If you used an installation usb drive created with Rufus, use Media Creation Tool. If you used the media creation tool, try a different usb drive. You just need a min. 8 GB usb drive.  Download the media creation tool again and install the new installation media on a different usb drive.

If your notebook came with Windows factory-installed, you could use HP Cloud Recovery Client software that restores the storage drive to a factory state. So let me know if your Windows came preinstalled or not.