错误原因：virtualbox版本与vagrant版本不对应，无法默认以virtualbox启动，导致用hyperv启动（开启hyperv也没用，会导致找不到离线下载的box），强制用virtualbox启动需要加上 --provider=virtualbox，加上后提示版本错误不对应，并且提示了可用版本。
Bringing machine 'default' up with 'hyperv' provider... ==> default: Verifying Hyper-V is enabled... The Hyper-V cmdlets for PowerShell are not available! Vagrant requires these to control Hyper-V. Please enable them in the "Windows Features" control panel and try again.
`PS D:vagrant est> vagrant up
Bringing machine 'default' up with 'hyperv' provider...
==> default: Verifying Hyper-V is enabled...
The Hyper-V cmdlets for PowerShell are not available! Vagrant
requires these to control Hyper-V. Please enable them in the
"Windows Features" control panel and try again.
PS D:vagrant est> vagrant up --provider=virtualbox
The provider 'virtualbox' that was requested to back the machine
'default' is reporting that it isn't usable on this system. The
reason is shown below:
Vagrant has detected that you have a version of VirtualBox installed
that is not supported by this version of Vagrant. Please install one of
the supported versions listed below to use Vagrant:
4.0, 4.1, 4.2, 4.3, 5.0, 5.1, 5.2, 6.0
A Vagrant update may also be available that adds support for the version
you specified. Please check www.vagrantup.com/downloads.html to download`