Exchange Online NDR When the reoccurring outlook meeting is updated and sent

Occasional Contributor
Can anyone help me to get the relevant information about following error and suggest the fix?
Error: STOREDRV.Deliver.Exception:StoragePermanentException.MapiExceptionInvalidParameter; Failed to process message due to a permanent exception with message Cannot modify recipients. 1.65506:00000000, 1.49122:22000000, 1.57314:00000000, 1.30670:00000000, 4.25550:57000780, 0.20017:02000000, 4.28209:57000780 [Stage: OnCreatedEvent][Agent: Meeting Message Processing Agent]'
Background of the issue: We have Exchange Hybrid but all users are hosted Exchange Online. One of the user recently tried to update a particular meeting event (from a reoccurring meeting) and countered following NDR from multiple users. In the original meeting the organizer had invited DLs as well. From the error I think the issue could be due to the new members were updated/added/removed in the groups but I can't find any relevant information online for this specific error... If you can find the valid reference which proves my suspicion it would be great.
6 Replies

@aanandkarki, Did you figure out this issue? We're having the exact same one as you.


It seems the meeting was created before migration. However, I am not sure if this will work, but you can try Meeting update Tool :




Nope I could not find the root cause but as a work around, I have removed the groups from the Meeting requests and cleared the cache and then resolved the name directly from GAL and sent the updated/modified request which fixed the issue.


I think it has something to do with DL membership caching.


Hello @aanandkarki ,

This issue occurs if the Clutter feature is enabled for the user but the Clutter folder is missing in the user’s mailbox.

To work around this issue, turn off Clutter for the user. To do this, use one of the following methods.

Method 1: Use Outlook on the web

  1. In Outlook on the web, click Settings in the upper-right corner.
  2. Click My app settings, click Mail, and then click Clutter.
  3. Clear the **Separate items identified as clutter **check box, and then click Save.

Method 2: Use Exchange Online PowerShell

  1. Connect to Exchange Online by using PowerShell. 

  2. Run the following command:


Get-Mailbox | Set-Clutter -Enable $false




In our case, neither mailbox has clutter enabled.