Copy and pasting email addresses from text file is not working

I have a 400+ email list I need to send a group email out to.

The email list is maintained in a text file.  When I copy and paste to the to field and send, I get ‘Non eof the email recipients were accepted by the server’.

This is a test email list I copied and pasted (edited to protect names):

Thanks in advance.

Hey Bill,

I recommend creating a .csv file from your text file and creating a distribution list. You can creat a distribution list in Contacts by right clicking and selecting New Distribution List - by importing the csv file in eM Client you can then add members to the distribution list from the address book.