Email Invoices Arent Being Sent

We have version that runs in batch for all orders at a status 580 to email invoices.

For whatever reason, the emails are not sending..

The customers are set as a V (Invoice) with send method 3 (email). The customers also have a valid email address loaded in the whos who.

If I run the job, I get output for all the invoices, but if I row exit and click "view delivery" it says "E1OUTQ". Typically this says the email address associated with the customer on the whos who.

Let me know if you need more details.