One of our user (userA) reported to us that when he tried to send on behalf of userB, the output is like below in the From field

userB On Behalf Of userB 

This is supposed to be userA On Behalf Of userB.

Upon checking, it only display on his end as when he attached the sent email to me it appears correct.

Any idea on the Outlook settings that might cause this?

Please note that we do not want to re-profile as we want to know the root cause if this is a bug or not. Thanks

Hi,

If the User A switch Outlook to Online Mode, check if the problem persists.

I suspect the issue is related to the Outlook Address Book, if you are using Cached Exchange Mode, please try to reset the Offline Address Book to check the result.

Browse to C:\Users\%username%\AppData\Local\Microsoft\Outlook, rename the folder name "Offline Address Books" to "Offline Address Books.old", Outlook will create a new one to sync the Address Book, check if the problem persists.

Regards,

Melon Chen
TechNet Community Su

Thanks for this input but the user is in online mode or non-cached mode.