Import error: no email field in template

Context

The spreadsheet import feature gives you the option of automatically setting up a member account for each new profile. This allows your members to log in and edit their own profile, without you needing to go through the grant-ownership step:

This process will use the email address of each profile to set up the login details for that profile. This means that an email address needs to exist for the profile.

What caused the error?

The template for the directory (that you set up in the Form Designer) didn't contain any email fields.

How can I fix the error?

Either un-check the checkbox in the screenshot above ("Add member account for each new profile"). Or add an email field to the directory template, in the Form Designer.