Outlook Mail Merge: Changing the default sending account
Mail merges use the default account in Outlook (usually your own account). If you manage secondary department accounts and want to send a mail merge from these accounts, follow these steps.
Change the default email account in Outlook.
Click File > Account Settings > Account Settings.
Select the account you want to send from and click ‘Set as Default’. Click Close.
Set Outlook to always use the default account to send new messages.
Click File > Options.
On the left click Mail.
Scroll down to the 'Send messages' section.
Enable “Always use the default account when composing new messages'.
Perform the mail merge. It should now be sent from the other account.
Revert the changes when you are done in order to set your own account back to the default.
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