An email can represent different things to different people; an invitation, a message, an update or a confirmation etc. If you dream about an email then this means that you have been waiting for something for a long time and now you feel relieved.
Seeing email in a dream signifies the dominance of words in our society. It is not just a communications technology, but it also symbolizes a private arena where one can perform self-expression and meditation on their life experiences.
Also, emailing in your unconscious mind implies that we have become too attached to electronics and cell phones in general. We often receive emails on our phones or computers as they are much more convenient to share via these modern devices compared to paper letters that take up space in the home or office.