Hi, I am an Exchange Hybrid Environment user and quite a new one at that. So, I want to differentiate between Dl’s created in Exchange Onprem and Office365 DL. What are they, what differentiates them between?
The only difference (for a standard DL, not O365 group, etc.) that I know is:
On-prem: Owners can change membership & can be more than 1 person
Hybrid/Online: They can’t.
There are a few limits which apply to Office 365 distribution groups that you should be aware of:
- Member count for a distribution list: 100,000 (50,000 for organizations using AAD Connect, 15,000 if there is a slightly outdated DirSync in place).
- Number of groups created by a single user/admin: 300,000.
- Number of distribution group owners: 10.
- Size for messages sent to groups with 5,000-99,999 members: 25MB.
The limits apply to all Office 365 subscriptions, it does not matter if you have Office 365 Business Essentials, or Office 365 Enterprise E5 subscription – the limits stay the same. The only difference is if you have Exchange Online as a standalone option. In this case, each plan allows one user to create up to 250 instead of 300,000 distribution groups.
Limits in exchange online for your reference.Distribution group limits