Yes - I can confirm the disk is not mounted, as per the link.
Are you sure that the disk is still identified as PhysicalDisk3 ?
Compare the number that is assigned in diskmanagement with the device referenced in the vmdk-descriptorfile.
Maybe trying to use the disk as a USB-device instead of a physical disk is an option for you.
See my notes: Virtual USB-disks | VM-Sickbay
That part is fine - I did check it. In fact Workstation obviously looks up some other hardware ID at the time, because at one point I did have another disk plugged in first, and when I tried, it reported the drive it could not access as PhysicalDisk4 - which at the time was the correct one.
I still have this problem - but I had given up trying - until recently. Issue still remains - have updated to Windows 10 1909, and re-installed WS 14.
Am I the only person with this problem?
Strange problem indeed.
My understanding is that the virtual machine is supposed to boot from that HDD, and not just use it as an additional hard disk for data, correct?
In my mind there are three scenarios. The first one is that the HDD has developed problems. The second is that the VMware installation or the VM settings are corrupt. The third is that both problems happen, or something particular to Windows 10 is at play (which maybe will need witchcraft to debug).
To address the first case, since you have a USB caddy available, I'd first check the disk's physical condition with Hard Disk Sentinel, to see if there are any bad sectors. Then I'd make a file system check (chkdsk) or a full surface check if bad sectors were found. Then I'd check whether the disk is active and bootable (use Disk Management).
For the second case, I'd recreate the VM from scratch: create a new Virtual Machine with the specifications for the OS that exists on the HDD. After that, add the physical disk manually via the Settings menu and delete the automatically made .vmdk file.
In the third case,I just hope somebody with more experience with Win10 will jump in to enlighten us...
Let me know if you find a solution. I have the exact same issue. I'm getting the same error with a Linux VM that 3 weeks ago I didn't have an issue with. I get the error when I reinstall VMware tools. I reverted back to a previous restore point in Windows. I was afraid that recent update I did was the problem but no luck so far. I'm using FTK to mount and have been doing this for years and never came across this error.