1. Access your email using "webmail." and your domain (i.e. webmail.yourdomain.com).
2. Sign in with your username (i.e. jsmith@yourdomain.com) and password.
3. Click the "Compose" icon at the top of the page. This will open up a new email message.
4. At this point, you can either type the file name in the text box at the bottom of the page where it says "Attach:", or use the browse feature to locate the file. Click on "Browse..." and use the new window to navigate through your system to locate the file you wish to attach. Once you have found it, click "Open." This will place the file's address in the text box.
5. Finally, click "Add" to attach the file to the email.

Please note that an email message can not have attachments cumulatively larger than 15 MB in size.