We are able to restrict all users and allow only specific groups or users to automatically book rooms in Office 365. To assign custom booking permissions for a resource mailbox, we need to login to the mailbox itself and modify the calendar permissions.
1.We need to give ourselves full access to the mailbox. Let’s navigate to the office 365 exchange admin center and locate the resource mailbox
- Double click the mailbox and go to Mailbox Delegation
- Scroll down to Full Access and select your account
2. Now for the second part, we need to login to our account in OWA. After we are logged we need to open the Resource Mailbox from our account.
- At the top right corner, click on your account picture and select “Open another mailbox”
- Enter the name of the mailbox and open it
3. Once we are in the resource mailbox, we need to go to Settings->View All Settings and select Calendar->Resource Scheduling
- Scroll down to Scheduling permissions and select “Specific people and groups”
- Add the specific users/group that would need access and save the settings
After this is all done, we can go back and remove ourselves from the Full Access permission to the mailbox.