Visit the Preferences module, open your JavaScript console and type "sieveCapabilities". What's the result?

Any news?

Same here (dovecot with default managesieve):

sieveCapabilities
<- Array [ ]

An empty array? Make sure SOGo can reach your Sieve server.

Well, ok. In my case, this really just was an issue connecting to the sieve server.

Sieve server is using TLS

====================================
telnet mx01 4190

Connected to mx01.
Escape character is '^]'.
"IMPLEMENTATION" "Dovecot Pigeonhole"
"SIEVE" "fileinto reject envelope encoded-character vacation subaddress comparator-i;ascii-numeric relational regex imap4flags copy include variables body enotify environment mailbox date ihave"
"NOTIFY" "mailto"
"SASL" ""
"STARTTLS"
"VERSION" "1.0"
OK "Dovecot ready."

If i'm using the Sieve plugin for thunderbird, i get a log entry like this:

====================================
mx01 dovecot: managesieve-login: Login: user=<me>, method=PLAIN, rip=xxx, lip=xxx, mpid=xxx, TLS, TLSv1.2 with cipher ECDHE-RSA-AES128-GCM-SHA256 (128/128 bits)

SOGo with SOGoSieveServer = sieve://mx01:4190 produces this:

====================================
mx01 dovecot: managesieve-login: Disconnected (tried to use disallowed plaintext auth): user=<>, method=PLAIN, rip=xxx, lip=xxx

Ok, playing around with SOGoSieveServer = sieve://mx01:4190/????!StartTLS also does not work.

For the moment, i just use a ssh tunnel to forward remote 4190 to local 4190 and set localhost as sieve server, then everything works as it should.

Same problem here. The used components are:

• server: IMAP/Sieve
  OS: CentOS/RHEL 7
  IMAP server version:
  • dovecot-2.2.10-5.el7.x86_64
  • dovecot-pigeonhole-2.2.10-5.el7.x86_64
• server: SOGo
  OS: CentOS/RHEL
  SOGo version: sogo-3.1.5.20160923-1.el7.centos.x86_64

Looks like there is no support for TLS sieve in SOGo?!

Configuration issue. Verify your SOGoSieveServer parameter:

https://sogo.nu/files/docs/SOGoInstallationGuide.html#_imap_server_configuration