"Allow to use Credentials for Email Processing" option under mailbox in Microsoft Dynamics CRM 2013 allow us to store credentials to access email services, if we are using Microsoft Dynamics CRM 2013 on-premise, we need to configure IFD to enable this options, but if you don’t want to configure IFD we have below workarounds to enable this open.
In this post we are going to discuss first option. We need a SSL certificate to bind with crm website. As we are using our demo VPC, so we have created a wild card certificate. Follow below steps to bind SSL certificate and configure https binding to crm website.
Now navigate to mailbox record in crm, you should get "Allow to use Credentials for Email Processing" enabled.