- download: MVMC
- (optional) edit with text editor vmdk file and remove (or comment out) all below line '# The Disk Data Base '
- run powershell as admin
- > Import-Module 'c:\Program Files\Microsoft Virtual Machine Converter\MvmcCmdlet.psd1'
- > ConvertTo-MvmcVirtualHardDisk -SourceLiteralPath source.vmdk -DestinationLiteralPath dest.vhdx -VhdType DynamicHardDisk -VhdFormat Vhd
or
qemu-img convert -f vmdk -O vhdx -o subformat=dynamic source.vmdk dest.vhdx