DKIM on outbound mails from WHMCS

[UpYoursIM]

Is it possible to add DKIM verification to all outbound mails coming from WHMCS? I'm using a new server (probably with no reputation) and almost every email is delivered to my junk mailbox. At this time, WHMCS is not sending to my customers, but somewhere in the next few weeks it will and I don't want those mails ending up in the junkfolders.
I did set an SPF record (which works), but still quite a few mails are marked spam.

[ganesh.rao]

DKIM is set by the mailserver.

If you are running cPanel/WHM, edit the account your WHMCS is hosted on and ticket the "enable SPF/DKIM" checkbox.

[UpYoursIM]

I tried that, but with no luck. Now I use an external mailserver (gmail) for sending the mail, this works. Thanks for your help anyway.