Hi Our Users are getting mails from post master@xxxxxxxxxx with some attachements (gif) stating that " the particular mail could not be delivered to recipient." Actually user is totally unaware of that mail. Some times the users are getting mails on behalf of some one else in our organization, with attachments . How can I stop this. I Have cleaned W32clez Virus from all the PC's and blocking harmful attachement from the server also.Expecting your valuable suggestions on this regards Thanking you Regards Aboo Arif Emcure Infotech Ltd. 2A/2, Kundan Estate, Bhaupatil Road Bhopodi Pune, Maharashtra 411020 Ph:5817111, 5817428, 29 www.emcureinfotech.com