"This message could not be sent" NDR when an approved user sends mail in Office 365

Applies to: Exchange Online

PROBLEM


When a user who has Send As permission to a distribution group tries to send an email message to other users by using Microsoft Outlook in Office 365, the user receives a non-delivery report (NDR) that contains the following error message:
This message could not be sent. Try sending the message again later, or contact your network administrator.
Error is [0x80070005-00000000-00000000]

CAUSE


This issue may occur if the address book in Outlook isn't updated. 

SOLUTION


To resolve this issue, follow these steps:
  1. Update the address book in Outlook. To do this, follow these steps.
    1. On the Office ribbon, click the Send/Receive tab, click the down arrow next to Send/Receive Groups, and then click Download Address Book.

      Screen shot of the Download Address Book command on the Send/Receive tab of the Office ribbon in Outlook
    2. In the Offline Address Book dialog box, make sure that the Download changes since last Send/Receive check box is selected and that Offline Global Address List is selected as the address book, and then click OK.

      Screen shot of the Offline Address Book dialog box, showing the
    3. Test to see whether the issue is resolved by sending an email message as the distribution group. When you create the message, use the global address list (GAL) to populate the From field.

      If doing this doesn't resolve the issue, go to step 2.
  2. Delete all files and folders in the Offline Address Books folder. To do this, follow these steps:
    1. Exit Outlook.
    2. Locate the Offline Address Books folder. In Windows 8 and Windows 7, the folder is located along the following path:
      \Users\<UserName>\AppData\Local\Microsoft\Outlook\Offline Address Books

      Screen shot of Windows Explorer, showing the path to the Offline Address Books folder

      Note
      The folder may be hidden. To unhide it, click Start, type folder options in the search box, click Folder Options, click the View tab, click Show hidden files, folders, and drives, and then click OK.
    3. Delete the contents of the Offline Address Books folder. (The contents of the folder will be re-created when you restart Outlook).
    4. Start Outlook, and then test to see whether the issue is resolved by sending an email message as the distribution group. 

MORE INFORMATION


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