Failed to map guest I/O buffer for write access with status 0xC0000044

How to Fix Hyper-V Server Virtual Machine Couldn’t Start Error: RemoteException: Failed to start virtual machine, Synthetic SCSI Controller.

Ahmet Doruk
3 min readDec 11, 2023
0xC0000044, virtual machine, hyper-v, error, disk, start

On the server with Hyper-v Server 2019 installed, one or more virtual machines failed and did not start due to a sudden shutdown of the server. Even though I tried several possible solutions to the error, I could not find a solution that worked completely. As a result of my experiments, I did a disk conversion operation to start the virtual machine and as a result, the virtual machine started.

Error Message

Message

RemoteException: Failed to start virtual machine Win10. Error:
'Win10' failed to start. Synthetic SCSI Controller
(Instance ID 76C7FC6C-F3DF-45F9–9842–265062DC540D):
Failed to Power on with Error 'Incorrect function.'.
Attachment 'C:\ProgramData\Microsoft\Windows\Virtual Hard Disks\
Win10\Virtual Hard Disks\Win10.vhdx'
failed to open because of error: 'Incorrect function.'.
'Win10' failed to start.
(Virtual machine ID 517C315C-7DD0–4CF6-AE28–8BCF9FA9FF92)
'Win10' Synthetic SCSI Controller
(Instance ID 76C7FC6C-F3DF-45F9–9842–265062DC540D):
Failed to Power on with Error 'Incorrect function.' (0x80070001).
(Virtual machine ID 517C315C-7DD0–4CF6-AE28–8BCF9FA9FF92) 'Win10':
Attachment 'C:\ProgramData\Microsoft\Windows\Virtual Hard Disks\Win10\Virtual Hard Disks\Win10.vhdx'
failed to open because of error: 'Incorrect function.' (0x80070001).
(Virtual machine ID 517C315C-7DD0–4CF6-AE28–8BCF9FA9FF92)

How to Fix Error

First, I’m going to open virtual machine settings and click “Disks

disk, hyper-v, 0xC0000044, Synthetic, SCSI, server, error

Click “Edit” and choose “Convert” at the action line. Disk format VHDX (I recommend if isn’t vhdx). Choose which one disk type works for you. Name of new VHDX and choose a new path. If you want to attach automatically vhd file after this process, choose the option. Then click edit.

disk, hyper-v, 0xC0000044, Synthetic, SCSI, server, error

When it's ready you will see the notification. After this notification you can delete old disk path.

disk, hyper-v, 0xC0000044, Synthetic, SCSI, server, error

As you can see I removed old disk.

disk, hyper-v, 0xC0000044, Synthetic, SCSI, server, error

It’s ready to work.

disk, hyper-v, 0xC0000044, Synthetic, SCSI, server, error, started succesfully

Virtual Machine works successfully. Also, you have new virtual disk without error and clean.

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