Unable to add full access on shared mailbox

Ramkrishna Trivedi 51 Reputation points
2022-02-18T10:41:43.3+00:00

Unable to grant full access to new users on the shared mailbox.
Is there any limit for Office 365 shared mailbox
getting below error:

The mailbox '' has reached the limit of maximum allowed access control entries of: 500. Clean existing entries and rearrange them leveraging
groups for assigning the same permission to multiple users.

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2 answers

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  1. Andy David - MVP 142.2K Reputation points MVP
    2022-02-18T12:30:29.443+00:00

    Yes: 500 per that message! :)

    You will need to create a group, give it access then add users to that group if you want to add more

    1 person found this answer helpful.
  2. Andy David - MVP 142.2K Reputation points MVP
    2022-02-18T13:38:47.667+00:00

    Does the mailbox have other delegates as well? SEND AS SEND on BEhalf, etc...

    https://learn.microsoft.com/en-us/answers/questions/518927/not-able-to-provide-send-as-permission-to-a-shared.html

    This has been seen before, others saw a limit of around 1000 but maybe its now 500