question

Hi,
to use Teams with your mail system, it needs to be a supported Exchange On-Prem (2016 CU3+) or Exchange Online.

How Exchange and Microsoft Teams interact
https://docs.microsoft.com/en-us/microsoftteams/exchange-teams-interact

If your mailbox is not on one of these system, your Calendar Add do not appear on Teams and there is no mail integration.

Best.
Luca

Hi MarcusRolloos-8820,

Do you mean that you want to use your business email address to book a Teams meeting in outlook client?

To schedule a meeting, open Outlook and switch to the calendar view. Click New Teams Meeting at the top of the view.

If Teams Meeting add-in in Outlook for Windows does not show, you can refer to this link to enable it: https://docs.microsoft.com/en-us/microsoftteams/teams-add-in-for-outlook#teams-meeting-add-in-in-outlook-for-windows-does-not-show.

Hello @MarcusRolloos-8820 ,

You can invite members to teams meetings by the following way

1. From Calendar app > New Meeting
   

2. 'Add Required Attendees' filed > You can type the email addresses need to be invited. Here, you can type any email address and not necessarily be within your team domain. That means, you can type email address in domains like Gmail, yahoo etc. too
   

3. Suppose, you need to add the attendees are to be filled automatically in 'Add Required Attendees' filed, you should have these emails added as contacts in your organization (Open Office 365 Admin Portal->Users->Contacts. If you have already added the outside email address as a contact in your organization, then no need to type the email address always, it can autofill the emails.

   
   

Please mark as "Accept the answer" if the above steps helps you. Others with similar issues can also follow the solution as per your suggestion

Regards,

Manu