We have a very large organization of several hundred thousand users. Many of our workers have 'Shared Mailboxes'. These shared-mailboxes have calendars for scheduling meetings.

However, one of our company's shared-mailboxes has a large number of users. So large in face, that they have divided into smaller groups. These different groups have then created additional calendars (sub-calendars) to this shared-mailbox. Thus far, no problem.

But, when one of these smaller groups attempts to send an invite to a meeting to one of these additional calendars (sub-calendars), that's when problems occur. The mailbox is not recognized, or "This meeting is not in the Calendar folder for this account. Responses to this meeting will not be tallied."

Sometimes (a rarity) a meeting goes through, but the user is then 'not' able to accept or decline. Those options for the user are grayed-out on the invitation.

Does anyone know of a way that meetings can be sent to 'sub-calendars'? and can they be operated as normal calendars?

Thank you. Any help would be appreciated.