Windows 10 1903 Restart zaps SSD drive letter

Start button > Power button > Restart = drive letter vanishes.

BUT

Start button > Power button > Shut down > PC power up = drive letter functions normally.

Dell XPS 8500
Processor Intel i7-3770
RAM 32GB

Windows 10 Home
Version 1903
Installed on 6/9/2019
OS build 18362.145

Samsung SSD 840 EVO 500GB
AHCI Mode Activated
TRIM Status Enabled
RAPID Mode On



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This is what happens after a Restart. All programs that use the SSD become nonfunctional!

thomaseg1 said:

I would turn fast boot off (there are a host of folks right here who have had problems with it).

Turn On or Off Fast Startup in Windows 10

I turned off fast boot (aka Fast Startup) and that made the problem worse. S: drive vanished from both Restart and PC power up. I turned Fast Startup back on. Even though your suggestion didn't solve the problem it did at least provide a clue as to the cause. Hopefully a Windows 10 boot expert will read this and come up with a solution. Thanks for your reply.

Been waiting 3 weeks and still no solution. SSD drive continues to disappear on Restart. Can somebody recommend a Microsoft support forum that has experts who could solve this problem?

Fast Boot is a mix of hibernation and fresh boot. It has a lot of issues. To start, turn it of on BIOS (If there is a Fast Boot option).
Then check if it is off under Windows (Brink tutorial)
After you initialize the SSD (create a partition and format), every time you shut down the computer it shows as not initialized?

Megahertz said:

Fast Boot is a mix of hibernation and fresh boot. It has a lot of issues. To start, turn it of on BIOS (If there is a Fast Boot option).
Then check if it is off under Windows (Brink tutorial)
After you initialize the SSD (create a partition and format), every time you shut down the computer it shows as not initialized?

The BIOS doesn't have a Fast Boot option. See picture below.

There is nothing wrong with my SSD. So it would be rather stupid to initialize it and lose 9380 files (224GB) of user data. The only time it shows as not initialized is after a Windows 10 Start button > Power button > Restart. That is the problem I'm trying to solve.

Can you recommend a Microsoft support forum that has experts who could solve this problem?

You seem to have the opposite problem to most! As I'm sure you know, Start>Power>Restart bypasses Fast Startup, which uses some partial hibernation. Itseems that your SSD is only visible after a fast restart, never (?) from a full cold boot. That suggests that the drive is not recognised from cold, but something happens subsequent to boot (maybe during the fast start reboot process) which makes it visible on the next (fast) start.

Do you have an 'HDD delay' option in the BIOS? I know that sounds odd, as it was (I think) designed to cope with slow devices (eg CD etc), and SSD's ought to be fast, but who knows? I feel I have read about your issue before, but don't know where.

bro67 said:

You are in the best forum for Peer to Peer. The missing hard drive letters is a bug in 1903 that was stated by MS in the beginning.

If the bug was stated by MS then is there a way to research it and determine its status? Is there a bug and/or update number like KBxxxxx? What does "in the beginning" mean?

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mngerhold said:

You seem to have the opposite problem to most! As I'm sure you know, Start>Power>Restart bypasses Fast Startup, which uses some partial hibernation. Itseems that your SSD is only visible after a fast restart, never (?) from a full cold boot. That suggests that the drive is not recognised from cold, but something happens subsequent to boot (maybe during the fast start reboot process) which makes it visible on the next (fast) start.

Do you have an 'HDD delay' option in the BIOS? I know that sounds odd, as it was (I think) designed to cope with slow devices (eg CD etc), and SSD's ought to be fast, but who knows? I feel I have read about your issue before, but don't know where.

BIOS doesn't have a "HDD delay" option.

Shut down + Fast Startup On = SSD found
Shut down + Fast Startup Off = SSD missing
Restart + Fast Startup On = SSD missing
Restart + Fast Startup Off = SSD missing

It seems likely that you will have to initialise the disk - but not yet! Boot it up via Fast startup and backup the data elsewhere, then initialise. If its MBR it may be possible to fix that (via command line or utilities), if GPT I think not (from my limited reading).