突然Vagrantが使えなくなった

MacOSを10.14.5にアップデートしたらVagrantが使えなくなった

なので
Vagrantを新しいVersionに入れ直したら

% vagrant -v
Vagrant 2.0.4

変なメッセージが出てきた
Virtualbox入っているのに、、、

% vagrant up
No usable default provider could be found for your system.

Vagrant relies on interactions with 3rd party systems, known as
"providers", to provide Vagrant with resources to run development
environments. Examples are VirtualBox, VMware, Hyper-V.

The easiest solution to this message is to install VirtualBox, which
is available for free on all major platforms.

If you believe you already have a provider available, make sure it
is properly installed and configured. You can see more details about
why a particular provider isn't working by forcing usage with
`vagrant up --provider=PROVIDER`, which should give you a more specific
error message for that particular provider.

Virtualboxを最新の6.0.10にしてもうまくいかず、、

色々試行錯誤した結果、以下の組み合わせでうまく行った

VirtualBox 6.0.4
Vagrant 2.2.5

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