Good morning, @gary5077.
Thanks for coming to the Community with your question about sending emails through your QuickBooks Desktop account.
QuickBooks requires recipients to be separated by a comma and a space, rather then a semicolon. This may be way you were able to send the email until after deleting the semicolon plus the other name.
I recommend trying this method to see if it works for you.
I hope this helps. Feel free to come back if you have any other questions or concerns. Have a splendid day!
