How can I edit a contact's email address?

The email address is the basis of a contact and cannot be changed manually. But there are two options how you can change them otherwise.

1) Fast version

You can create a new contact with the correct email address via file upload or manual entry and afterwards delete the old contact. Please keep in mind that the profile of the contact will 

2) Safety version

In order to keep the data of the contact, but still update the email address, the adjustment must be made by the contact himself. For this Option you have to use the contact profile form. How to create and use this form you can read here.