Salesforce: noreply@salesforce.com on behalf of

When you send email from Salesforce, for recipient open the email sent with Microsoft Outlook, the may see the sender as noreply@salesforce.com on behalf of Sender FirstName LastName <emailaddress@domain.com> rather than your name and your email address.

But, when recipient hit reply in Microsoft Outlook, it will point the email to "the right email address" of the sender, not to no-reply@salesforce.com

When recipient open the same email not with Microsoft Outlook, example: using gmail.com, the sender "noreply@salesforce.com on behalf of" is not there. Salesforce is not adding that into the email, that is caused by the email client, which is specific to Microsoft Outlook. Below is screenshot from other email client:

To remove "noreply@salesforce.com on behalf of" follow these steps:

• Click on Setup | Email Administration | Deliverability 
• Locate the Email Security Compliance section
• Unselect the Enable Sender ID compliance box 
• Click Save button

The emails you send will no longer include the "noreply@salesforce.com on behalf of".

This is how it looks when open from other email client (such as: gmail.com), notice there are no differences before and after we change Sender Id compliance.

Reference:

• Remove "noreply@salesforce.com on behalf of" when sending an email from Salesforce