ADE: VolumeType "" is not supported

I tried to encrypt a markeplace Ubuntu VM (Image:Canonical:UbuntuServer:16.04-LTS:latest,Size:Standard_DS3_v2) OS disk using **Powershell**.
AzureDiskEncryptionForLinux version is 1.1.0.17

The encryption process work when I used **azure cli** instead of **Powershell**, same image and same size.

**Cloudshell**]:
```
PS Azure:\> Set-AzureRmVMDiskEncryptionExtension -ResourceGroupName $resourceGroupName -VMName $VMName -DiskEncryptionKeyVaultUrl $DiskEncryptionKeyVaultUrl -DiskEncryptionKeyVaultId $KeyVaultResourceId –SkipVmBackup

Enable AzureDiskEncryption on the VM
This cmdlet prepares the VM and enables encryption which may reboot the machine and takes 10-15 minutes to finish. Please save your work on the VM before confirming. Do you want to continue?
[Y] Yes [N] No [S] Suspend [?] Help (default is "Y"):
Set-AzureRmVMDiskEncryptionExtension : Long running operation failed with status 'Failed'. Additional Info:'VM has reported a failure when processing extension 'AzureDiskEncryptionForLinux'. Error message: "VolumeType "" is not supported".'
ErrorCode: VMExtensionProvisioningError
ErrorMessage: VM has reported a failure when processing extension 'AzureDiskEncryptionForLinux'. Error message: "VolumeType "" is not supported".
ErrorTarget:
StartTime: 10/12/18 12:57:52 AM
EndTime: 10/12/18 12:59:37 AM
OperationID: 39f46ffc-ceed-47c5-b3d4-cfa7b2bcf37a
Status: Failed
At line:1 char:1
+ Set-AzureRmVMDiskEncryptionExtension -ResourceGroupName $resourceGrou ...
+ ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
+ CategoryInfo : CloseError: (:) [Set-AzVMDiskEncryptionExtension], ComputeCloudException
+ FullyQualifiedErrorId : Microsoft.Azure.Commands.Compute.Extension.AzureDiskEncryption.SetAzureDiskEncryptionExtensionCommand
Azure:/
PS Azure:\> Get-AzureRmVMDiskEncryptionStatus -ResourceGroupName $resourceGroupName -VMName $VMName

OsVolumeEncrypted : NotEncrypted
DataVolumesEncrypted : NotMounted
OsVolumeEncryptionSettings :
ProgressMessage : VolumeType "" is not supported
```

**extension.log**:
```
2018/10/12 00:59:30 [Microsoft.Azure.Security.AzureDiskEncryptionForLinux-1.0]: 9066: [Info] Unsupported volume type specified and BEK volume does not exist, clearing encryption config
2018/10/12 00:59:30 [Microsoft.Azure.Security.AzureDiskEncryptionForLinux-1.0]: 9066: [Info] archiving the encryption config file: /var/lib/azure_disk_encryption_config/azure_crypt_config.ini
2018/10/12 00:59:30 [Microsoft.Azure.Security.AzureDiskEncryptionForLinux-1.0]: [StatusReport (0)] op: EnableEncryption
2018/10/12 00:59:30 [Microsoft.Azure.Security.AzureDiskEncryptionForLinux-1.0]: [StatusReport (0)] status: error
2018/10/12 00:59:30 [Microsoft.Azure.Security.AzureDiskEncryptionForLinux-1.0]: [StatusReport (0)] code: 17
2018/10/12 00:59:30 [Microsoft.Azure.Security.AzureDiskEncryptionForLinux-1.0]: [StatusReport (0)] msg: VolumeType "" is not supported
2018/10/12 00:59:30 [Microsoft.Azure.Security.AzureDiskEncryptionForLinux-1.0]: 9066: [Info] Executing: lvs --noheadings --nameprefixes --unquoted -o lv_name,vg_name,lv_kernel_major,lv_kernel_minor
2018/10/12 00:59:30 [Microsoft.Azure.Security.AzureDiskEncryptionForLinux-1.0]: [StatusReport (0)] substatus: {"os": "NotEncrypted", "data": "NotMounted"}
```

There is only the following file in */var/lib/azure_disk_encryption_config/*:
```
# cat /var/lib/azure_disk_encryption_config/azure_crypt_config.ini_2018-10-12\ 00\:59\:30.101709
[azure_crypt_config]
volumetype =

#
``