Yesterday I emailed 143 people. 1 emailed shows as delivered, the rest soft bounced. Any ideas why that might occur? I can certainly understand some soft bounces but 142/143 is a bit much... wondering if there is something I did wrong.
Do you have SPF and DKIM set up? It will tell your recipients' email clients that Marketo is authorized to send emails on behalf of your company. If SPF and DKIM isn't set up your email will be flagged as unauthorized spam.
Information on setting up SPF and DKIM: https://community.marketo.com/MarketoArticle?id=kA050000000KyrDCAS