Configuring Delegate access via PowerShell.

Occasional Contributor

delegate access.png

Is the following window configurable at all via PowerShell? lots of Googling brings up various options and none seem to work.


(this is in relation to the box below specifically)



Things I've noted:


Delegates set here are "ResourceDelegates" for the Get-CalendarProcessing output, but you can't use

Set-CalendarProcessing as it only works on resource mailboxes (Error : "ResourceDelegates can only be enabled on resource mailboxes.")


Under Get-MailboxFolderPermission user:\calendar you can also see the delegates setup, and with a SharingPermissionFlags of "Delegate, CanViewPrivateItems" (if set when adding them via the GUI above) but using Set-MailboxFolderPermission or Add-MailboxFolderPermission you can't seem to set those flags. 


Anyone had any ideas? hooking into EWS perhaps?



9 Replies
best response confirmed by Ben Harris (Occasional Contributor)

It will be doable via PowerShell in few days, I cannot share more until the official documentation is posted. Until then, you can use EWS to manage them, there's a good module here:


If using EWS seems to complicated, just wait a bit :)

Awesome thank you, can you let me know when it gets released?





It is already rolling out :)



  Updated feature: Manage calendar delegate permissions in PowerShell 


Stay Informed

Published On : February 16, 2018

We’re improving the MailboxFolderPermission cmdlet. This feature began rolling out this week. This message is associated with Office 365 Roadmap ID: 26355. With this update, you can now manage calendar delegate permissions from the *-MailboxFolderPermission cmdlet.

Has anyone ever seen this error when trying to set delegate sharing permission flags in Powershell?

"Failed to update delegateCollection"

I have retried a few times on this luck

If you can reliably reproduce the issue, capture the transcript and open a support case.

Did you find a solution? I get the same error when using the command -SharingPermissionsFlags Delegate.

Yes, it was an odd fix but Microsoft had me clear the user's local free/busy time using MFCmapi and that resolved the issue. It did take a while to replicate so after you remove the free/busy info, wait a day then try again.


I hope this is rolled out to on premises (2013/2016) via a CU soon

@Vasil Michev - This feature has STILL not been rolled out to Exchange 2016 on-prem users.  We have a hybrid environment using 2016.  Is this feature ever going to be pushed to on-prem servers?