Install the modules

 

1) Open Windows PowerShell as an administrator (use Run as administrator).

2) Run this command, and enter Office 365 Global Admin credentials.

$credential = Get-Credential

3) Run these commands to connect to Office 365.

Import-Module MsOnline

Connect-MsolService -Credential $credential

4)Run these commands to connect to SharePoint Online. Replace your-tenant with the actual value for your domain.

Import-Module Microsoft.Online.SharePoint.PowerShell -DisableNameChecking

Connect-SPOService -Url https://your-tenant-admin.sharepoint.com -credential $credential

Get-SPOSite

Get-sposite https://your-tenant.sharepoint.com/Site location

Look at Sharing Capability

To change

what one you type to change to

“Disabled” – external user sharing (share by email) and guest link sharing are both disabled

“ExternalUserSharingOnly” – external user sharing (share by email) is enabled, but guest link sharing is disabled

“ExistingExternalUserSharingOnly” – (DEFAULT) Allow sharing only with the external users that already exist in your organization’s directory

“ExternalUserAndGuestSharing” – external user sharing (share by email) and guest link sharing are both enabled

 

Set-SPOSite -Identity your-tenant.sharepoint.com/Site location -SharingCapability ExternalUserSharingOnly