Import error: no data found for email

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, and also that a column in the spreadsheet needs to be mapped to that field.

What caused the error?

One or more of the rows being imported from the spreadsheet, did not contain an email address in the column(s) that were associated with the email address field.

How can I fix the error?

Either un-check the checkbox in the screenshot above ("Add member account for each new profile"). Or make sure that all the rows in the spreadsheet that are being imported, have data in the email column.