Couldn't open file /lt-Homestead-3-0-0-2017082400/metadata.json，出现这个报错要怎么处理？

$ cd ~/Homestead && vagrant provision && vagrant reload

==> homestead-7: Attempting graceful shutdown of VM...
==> homestead-7: Checking if box 'laravel/homestead' is up to date...
==> homestead-7: There was a problem while downloading the metadata for your box
==> homestead-7: to check for updates. This is not an error, since it is usually due
==> homestead-7: to temporary network problems. This is just a warning. The problem
==> homestead-7: encountered was:
==> homestead-7:
==> homestead-7: Couldn't open file /lt-homestead-3-0-0-2017082400/metadata.json
==> homestead-7:
==> homestead-7: If you want to check for box updates, verify your network connection
==> homestead-7: is valid and try again.