Limits on the amount of delegator in Outlook

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Hello,

I have a question regarding the amount of Mailbox that can be managed by a user that was delegated the permissions to manage a Mailbox. How many delegators can a delegue can manage?

I have never heard mention of any kind of limit on this. I know that it was intended for a single person really - for example, your assistant. But I am thinking there is no real hard limit.

https://docs.microsoft.com/en-us/microsoft-365/admin/add-users/give-mailbox-permissions-to-another-user?view=o365-worldwide

@Anthony-Sequeira Hello, Exchange on premises. No 365.

@Jp-Alcan ,

I cannot find a reference to any limitation as to how many mailboxes a user can be delegated access to. I don't believe there is a limit, since you are simply adding a user to an access control list. Have you run into a problem delegating access to multiple mailboxes?

@Mike-Rodrick Hello, for the moment I am just unable to get one mailbox delegated to one user and this is why I am asking whether there is a limit to how many delegators she can manage.

However, there is a document that says that no more than 4 delegates for one delegator should be used as part of best practices, and in this case, I could not get a person to delegate the meetings for the delegator for S4B.

https://support.microsoft.com/en-us/office/best-practices-for-organizations-when-using-the-outlook-calendar-d93f72d3-2361-4e0d-8d6a-5c4939c17f39?ui=en-us&rs=en-us&ad=us

@Jp-Alcan ,

Thanks for the link!

It seems the recommended limit is more of a security / administration limit. They suggest only delegating editor permissions over a mailbox to one user for accountability reasons. They also suggest with too many users delegated permissions over the same mailbox, there could be performance issues.

It doesn't seem to suggest there is any limit on how many mailboxes a user can be delegated access to.

So one assistant could be delegated access to many mailboxes. You wouldn't want multiple assistants, or less than four at least, to have delegated access to the same mailbox.

What method are you using to delegate access, and what error are you receiving?

@Mike-Rodrick Hello, The only error I am getting is that "You do not have permission to schedule Skype meetings on behalf of the owner”
For the initial question, the error is the inbox is not expanding and states that "Mailbox can not expand ". When I add the MB like adding an FMB after adding the permissions
However, and this is new. If I do open other user's folder, then the emails are viewable but in the delegate's inbox and mixed with the email's of the delegate.

@Jp-Alcan Today I resolved the delegation of S4B

delete
\HKEY_USERS\S-1-5-21-8915387-2032300435-1842888061-52869\Software\Microsoft\Office\16.0\Lync
reboot machine
On S4B profile
Select Tools > Options > Call Forwarding Settings.
Select Edit my delegate members. remove user add user.
The user can delegate meeting on behalf of delegator

I think the other issue maybe the same way. Thanks for your help.

@Jp-Alcan ,

Glad you figured it out! I wasn't having any luck.