Turn On DKIM Signing

Hi Gopal, if you review this Marketo doc it will provide you with a guide to set up your DKIM and SPF records.  

Hi,

I am not sure I understand the question, but you can go to admin -> email then on the top of the screen, click the SPF/DKIM tab. From there, you will be able to add domains and Marketo will provide you with the DKIM entry for each domain you add.

Once you have added the DKIM (and SPF) entries in the domain DNS, you come back here and validate the domains.

The full doc is here : Set up SPF and DKIM for your Email Deliverability - Marketo Docs - Product Docs

Please note that each domain may have a different DKIM key, so do not use the same for every domain.

-Greg

And the last thing to note is that once you have verified your domain that you added, it means that any emails being sent out of Marketo with a From Address that uses the same domain, it will be signed automatically.