I am running Windows NT 4.0 and Exchange 5.5 spa 4. I would like to know the maximum number of mailboxes and custom recipients I can configure. Currently we are running a client based airline bonus which we give to our premium class clients and we need to send about 30,000 clients mail which we believe will clog the Exchange server. Can someone advise. regards Thomas Kamire DISCLAIMER: This message and any attachments are confidential and may be legally privileged or otherwise protected from disclosure. Although the necessary precautions have been taken, Kenya Airways does not accept legal responsibility for any damage whatsoever that is caused by viruses being passed or for the contents of this message. This message, and any attachments, are intended solely for use by the named addressee. If you are not the intended recipient, you must not copy them or disclose their contents to any other person. If you have received this message in error, please notify the sender by return e-mail and delete any attachments accompanying it immediately.