Hi, I use sis to deduplicate attachments, here is my doveconf -n

auth_cache_size = 10 M auth_failure_delay = 5 secs auth_mechanisms = plain login auth_socket_path = /var/run/dovecot/auth-userdb auth_ssl_username_from_cert = yes auth_username_format = %Ln default_vsz_limit = 512 M lmtp_rcpt_check_quota = yes mail_attachment_detection_options = add-flags-on-save mail_attachment_dir = /var/mail/mail_attachment/ mail_debug = yes mail_gid = vmail mail_location = maildir:/var/mail/%n/Maildir mail_plugins = quota fts fts_solr mail_privileged_group = vmail mail_uid = vmail managesieve_notify_capability = mailto managesieve_sieve_capability = fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date index ihave duplicate mime foreverypart extracttext namespace inbox { inbox = yes location = mailbox Drafts { special_use = \Drafts } mailbox Junk { auto = subscribe special_use = \Junk } mailbox Sent { auto = subscribe special_use = \Sent } mailbox Trash { auto = subscribe special_use = \Trash } prefix = } passdb { args = /etc/dovecot/dovecot-ldap.conf.ext driver = ldap } plugin { fts = solr fts_autoindex = yes fts_autoindex_exclude = \Junk fts_autoindex_exclude2 = \Trash fts_solr = break-imap-search url=http://localhost:8983/solr/dovecot/ quota = maildir:User quota quota_grace = 10%% quota_max_mail_size = 5M quota_over_flag_lazy_check = yes quota_over_flag_value = TRUE quota_rule = *:storage=100M quota_warning = storage=65%% quota-warning 65 %u quota_warning2 = storage=60%% quota-warning 60 %u sieve = file:~/sieve;active=~/.dovecot.sieve } protocols = imap lmtp sieve service auth-worker { user = $default_internal_user } service auth { unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0640 user = postfix } unix_listener auth-userdb { mode = 0777 user = $default_internal_user } user = $default_internal_user } service imap-login { inet_listener imap { port = 0 } inet_listener imaps { port = 993 ssl = yes } } service managesieve-login { inet_listener sieve { port = 4190 } process_min_avail = 0 service_count = 1 vsz_limit = 128 M } service pop3-login { inet_listener pop3 { port = 0 } inet_listener pop3s { port = 0 } } service quota-warning { executable = script /usr/local/bin/quota-warning.sh unix_listener quota-warning { user = vmail } user = vmail } service stats { unix_listener stats-writer { mode = 0666 } } service submission-login { inet_listener submission { port = 0 } } ssl = required ssl_cert = </etc/ssl/certs/dovecot.pem ssl_dh = # hidden, use -P to show it ssl_key = # hidden, use -P to show it userdb { driver = prefetch } userdb { args = /etc/dovecot/dovecot-ldap.conf.ext default_fields = home=/var/mail/%u driver = ldap } protocol !indexer-worker { mail_vsize_bg_after_count = 0 } protocol lda { mail_plugins = quota fts fts_solr sieve } protocol imap { mail_max_userip_connections = 5 mail_plugins = quota fts fts_solr imap_quota } protocol lmtp { mail_plugins = quota fts fts_solr }

I try to send an email and then forward this email to another recipient. No attachment is generated in mail_attachment_dir.

Anything wrong ?