Outlook sending attachements errors with TrendMicro

All of a sudden my client could not send large attachments. Got this error:Sending' reported error (0x800CCC0B) : 'Unknown Error 0x800CCC0B'Task - Sending' reported error (0x8004210B) : 'The operation timed out waiting for a response from the sending (SMTP)Outlook 2007 was installed along with Trend Micro Internet Security. It was timing out on the send. Found it to be the scanning of large