Difference in Email notification while sharing Site, List/Lib and List/Lib Items

In SharePoint 2019 On-Premises, the behavior you are experiencing regarding email notifications when sharing sites, lists/libraries, and list/library items can be attributed to the configuration of outgoing email settings.

When you share a site or a list/library, the email notifications are sent from your email address because the sharing action is typically initiated by you, and SharePoint uses your email for this purpose. However, when you share individual items within a list or library, the notifications are sent from the generic account specified in the SharePoint outgoing email settings. This is because item-level sharing may be configured to use the outbound SMTP service for notifications, which defaults to the generic email account set in the outgoing email configuration.

To change this behavior, you may need to review the outgoing email settings in SharePoint Central Administration and ensure that the appropriate settings are configured for item-level notifications, if such customization is supported in your environment.

Hi @Gaurav Sharma

Thank you for posting your question in the Microsoft Q&A forum.

I know this is a little bit confusing between sharing a site/library versus sharing a list item/ folder item.

Based on my research, sharing an item relies on notification system that you have set up in outgoing email (Outbound SMTP server). Which is why the user is seeing the email from a generic account.

Additionally, outgoing email settings at the web application-level override those set up at the server farm level. You can also specify different settings for a specific web application.

From this document, Email impersonation, some SharePoint features might impersonate end user address, most likely site-level actions. For item/file-level, SharePoint uses notification (alert) system

If I misunderstand anything, please correct me. I hope this information helps.

Reference: Plan outgoing email for a SharePoint Server farm - SharePoint Server | Microsoft Learn

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