Giving all users Reviewer access to a mailbox calendar (works on resource calendars too)

Connect to Office365 Exchange online or open your local Exchange PowerShell.

Set-MailboxFolderPermission "MailboxName:\calendar" –User default –AccessRights reviewer

Some Hyper-V guests loose network connectivity

Host has network, some guests have network and some do not.

It's a known problem with some network drivers and an update will resolve the issue, however you can also turn off a feature for a live running fix.

Set-NetAdapterVmq -Name "NIC 1" -Enabled $False