Hi, I've been working with dovecot SiS for a long time without any problem. This is my configuration for SiS: mail_attachment_dir = /mail/users/attachments mail_attachment_fs = sis posix mail_attachment_hash = %{sha1} mail_attachment_min_size = 128 k With this configuration, I have, for example: # ls -l /mail/users/attachments/27/d1/27d1904ac9947945bf48ea545ec278940d840ed1* -rw------- 12 vmail vmail 142914 may 6 2013 /mail/users/attachments/27/d1/27d1904ac9947945bf48ea545ec278940d840ed1-090d88269ad28851f14b0000a9061514 ... And every file is a hard link to /mail/users/attachments/27/d1/hashes/27d1904ac9947945bf48ea545ec278940d840ed1 For the documentation I have found, "27d1904ac9947945bf48ea545ec278940d840ed1" is a hash of the attach content, but what does the other part of the filename (the "090d88269ad28851f14b0000a9061514" means) My question has come to my mind because I need an easy way to find the mailbox where this attach is referenced from. -- Angel L. Mateo Mart?nez Secci?n de Telem?tica ?rea de Tecnolog?as de la Informaci?n y las Comunicaciones Aplicadas (ATICA) http://www.um.es/atica Tfo: 868887590 Fax: 868888337