If you have your email server set up so that emails received are automatically forwarded into your CRM account - by sending a copy of the email into your CRM dropbox email address for example:
yourcompanyname@mail.crmdomain.com
Then emails you receive in from contacts can be seen on the Dashboard and inside the contacts record - within the History section.
If your account is set up so that only emails from 'known' contacts i.e. where contacts exist inside the CRM system with their email address recorded then you will only see emails from these known contacts recorded.
Emails you receive but (are from email addresses which are not stored inside your CRM system) will be from 'unknown' contacts - whose contact record and email address are not stored inside your CRM account.
Please check with us to see if your account is set up to block emails from 'unknown' contacts by emailing our Support Helpdesk.