changes to the address that is used to send notification email messages from SharePoint

Hi @Ronny Cornelis ,
The email messages are sent from a mail-enabled security group such as 'no-reply@sharepointonline.com'. When a Microsoft 365 group receives a message from such a security group, it treats the address as external and blocks it. This blocking occurs because Microsoft 365 groups aren’t allowed to receive email messages from external addresses by default.
To resolve the issue of blocked email messages, change the settings of the Microsoft 365 group to allow email messages from external addresses:
Open the Microsoft 365 admin center.
Select Teams & groups > Active teams & groups.
Search for and select the group whose settings you want to change.
Select the Settings tab.
Under General settings, select Allow external senders to email this group.
Note: This setting will allow email messages from any external address to be sent to the group.
Select Save.
Note: If the members of the group subscribe to receive copies of all the email messages that are received by the group, they can see the notifications either in their Inbox or in their Junk Mail folder depending on their individual mailbox settings.
For more information, please refer to:
https://zcusa.951200.xyz/en-us/sharepoint/troubleshoot/sites/notification-email-not-received
https://www.codetwo.com/kb/configure-groups-for-autoresponder/#:~:text=Fig.-,1.,%2C%20and%20click%20Save%20(Fig
Note: Microsoft is providing this information as a convenience to you. The sites are not controlled by Microsoft. Microsoft cannot make any representations regarding the quality, safety, or suitability of any software or information found there. Please make sure that you completely understand the risk before retrieving any suggestions from the above link.

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Hi,

Thanks for your answer.

That's just one of the problems.
We cannot make all distribution lists publicly available.
Together with our DPO, it was decided not to do this for security reasons.

Is there another option to resolve this?

The From display name is no more overwritable. Before we had a user "Exampe User" no-reply@sharepointonline instead now, without changing anything, the e-mail received show us "SharePoint Online" no-reply@sharepointonline. Is there an issue in Sharepoint? that happened since December 2023. Thanks.