Booking a conference room with another email/company

Question

Hello,
We have installed screens and email accounts to our conference rooms so people can book the rooms on Outlook. Each room is connected to a different license and email and the request is automatically replied to whoever makes the booking. However we have employees from different companies who wish to all be able to book conference rooms.
Our rooms are connected to @company1 but we also need that people with email adresses @company2 and @company3 are able to book the same conference rooms if needed.

How can we change this in our already installed conference booking solution?

Answer 1

Are those companies all using their separate Office 365 tenants? If so, you need to enable external meeting processing on each room mailbox:

Set-CalendarProcessing roomname -ProcessExternalMeetingMessages $true  

If the companies are all using the same tenant, this is available out of the box.