Why a Mailchimp email row can fail.

For an email-contact import, each row needs one valid Email Address. Extra spaces, missing address parts or unsupported characters can stop a row from importing.

International characters before the @

Mailchimp can handle international characters in the domain side of an address, but not UTF-8 characters in the local part before the @. ReadyRows flags those rows rather than rewriting somebody's address.

Provider typos

Common misspellings of major provider domains can also be rejected. ReadyRows warns about likely typos such as a Gmail or Yahoo misspelling but leaves the final correction to you because changing an email address is not always safe.