I have created a Contact Group with approximately 120 email addresses. I have tried to send an email and I receive this error message: Sending reported error (0x800CC0F): The connection to the server was interrupted. If this problem continues, contact your server administrator or ISP. The server responded: 501 Too many syntax or protocol errors.
I searched for a solution and it appears that the main reason this occurs is because of wrong characters in the email addresses. I have checked that the email addresses and they are perfect. There are no quotation marks, brackets or spaces in the email addresses.
I don't know what to do next to resolve this problem.