Question: how large is this EPS file you are trying to email? You should not email any file larger than 5 MB. Instead, you should use some kind of FTP program or web file sharing site such as DropBox or YouSendIt.
Also, you should compress the file into either a .zip or .sitx file before attaching it to an email, even if it is under 5 MB in size.
Since you are using a MacBook Pro, select the file in the Finder and under the File Menu choose "Compress..."; this will compress the file into a .zip archive. Then, attach that file to your email.