- dovecot - dovecot.org

Search for missing To: header?
by Joseph Tam 20 Feb '26

20 Feb '26

Is there a proper way to torture doveadm search query to look for messages with a missing "To:" header? I played around with it and this seems to work: doveadm fetch -A text mailbox {box} NOT TO '' (Looking through a large spam corups: spam often exclude recipients in the headers as it gives the game away their personalized fraud was blasted to hundreds of addresses.) Joseph Tam <jtam.home(a)gmail.com>

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More Dovecot 2.4 woes: LDAP cache bug and virtual autosubscribe
by sev monster 19 Feb '26

19 Feb '26

8 months ago I messaged this list communicating some of the issues I had with 2.4. Before I could even start testing 2.4 properly, 2 bugs had to be fixed—one that caused crashes on startup (https://gitlab.alpinelinux.org/alpine/aports/-/issues/17050) and one that caused passdb to use the same caching key for all connections and as such always have the same user log in. There was another bug, one that prevented me from using LDAP binds for passdb, but it had a workaround that mostly worked without side-eeffects. All of those have since been fixed, hurray! So in my infinite naïveté, I decided to give 2.4 another shake. And it, again, does not work. Surprise! I did manage to massage the configuration to allow me to at least run 2.4 without crashing and with users able to access (most of) their mailboxes, but there are still blockers to full functionality. I face the following issues: 1. Christian Pfeiffer back in November found a bug where auth caching with LDAP did not work, and due to how it's implemented, even turning caching off would still raise an error. I experienced the same issue for both userdb iteration and passdb bind logins. I had to comment out the userdb and use a static one instead (all my users, currently, use the same UID and easily composable path, so this wasn't a big deal) and start using a service account for LDAP binds. 2. Virtual mailbox autosubscribe does not work anymore. It throws an error about trying to create the virtual mailbox. This worked in 2.3. My virtual mailbox config: namespace virtual { type = private prefix = Search Folders. mail_driver = virtual mail_path = /etc/dovecot/virtual mail_index_path = ~/dovecot-virtual.cache mail_control_path = ~/dovecot-virtual.cache mail_volatile_path = ~/dovecot-virtual.cache hidden = yes list = children subscriptions = no mailbox All { auto = subscribe special_use = \All comment = All messages, excluding Junk and Trash } mailbox Unread { auto = subscribe special_use = \Important comment = All unread messages, excluding Junk and Trash } mailbox Flagged { auto = subscribe special_use = \Flagged comment = All flagged messages } } If there is something wrong with this config that might be responsible for my issue, please let me know. Otherwise, I believe this is a regression. I understand autosubscribe is documented to (and in other situations with non-virtual boxes) create mailboxes if missing, so if this is actually a fix to make the feature work as documented, we need a new option that allows for autosubscription without attempting to create the mailbox. Otherwise, my users will not know they even have these mailboxes—no one anymore knows or cares about mailbox (re: folder) subscription and won't know where to look to get them to show up in their client. With autosubscribe enabled, I can see the mailboxes in my mail client without explicitly subscribing, but attempting to open them will throw a server error. Removing the setting will make the mailbox disappear without going into settings and explicitly subscribing. Any ETA on the first bug being fixed, and any help with the second issue (bug or not) would be greatly appreciated. Best regards. P.S.: I wanted to spread this information that wasn't mentioned at all in the documentation. The shadow passdb was removed in the move to 2.4; why exactly is neither here nor there, though I will remark that I still don't know why it was done. I had believed at the time this necessitated enabling PAM for Dovecot, which it is not by default in my distro's package (Alpine), so if I wanted to continue allowing local users to log in, I would have to build Dovecot it myself and install PAM, neither of which I particularly wanted to do. I did play with passwd-file in the past, but there were issues with it that prevented me from using it—I don't remember what they were exactly, but I believe they have since been fixed, since in my testing now it does seem to work properly in the use-cases I tested. Anyway, while going over my config and getting ready to re-install PAM, I had a thought. /etc/shadow uses the same format for the first two fields as /etc/password, and Dovecot still (supposedly) allows for passwords to be used when reading /etc/password, so wouldn't it be possible to point the driver at the shadow file? Turns out, yes, it works! I am now able to authenticate local users from /etc/shadow again. Thanks to this, I no longer need to build with PAM support and don't need to install PAM on a PAM-less system. I hope this isn't considered a bug or something and support for this use-case is removed, because I really don't want to bother once again with adding PAM when I don't have to. :)

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Fedora 43 and Dovecot version 2.4.2
by Bill Steinberg 19 Feb '26

19 Feb '26

Hello, I am running Fedora 43 on a server which is running a dovecot server, version 2.4.1-8. I am not running a cluster, there is only one dovecot server running on the Fedora 43 instance. Redhat has just updated the dovecot version on Fedora 43 to version 2.4.2-5. I would like to upgrade dovecot to version 2.4.2. I assume that the dovecot_config_version should be changed to 2.4.2. Should the dovecot_storage_version be changed to 2.4.2 as well? Are there any steps that should be taken to upgrade the dovecot storage to version 2.4.2? FYI the mail_driver on the dovecot server is mbox: mail_driver = mbox. Best regards, -Bill Hello, I am running Fedora 43 on a server which is running a dovecot server, version 2.4.1-8. I am not running a cluster, there is only one dovecot server running on the Fedora 43 instance. Redhat has just updated the dovecot version on Fedora 43 to version 2.4.2-5. I would like to upgrade dovecot to version 2.4.2. I assume that the dovecot_config_version should be changed to 2.4.2. Should the dovecot_storage_version be changed to 2.4.2 as well? Are there any steps that should be taken to upgrade the dovecot storage to version 2.4.2? FYI the mail_driver on the dovecot server is mbox: mail_driver = mbox. Best regards, -Bill

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deliver fails because of a permission issue with SSL private key file
by Markus Schönhaber 19 Feb '26

19 Feb '26

Hi, I'm trying to make Postfix hand incoming mail to Dovecot by using Dovecot's deliver. But this fails with a permission error: > Feb 17 15:50:12 debian13-cont postfix/pipe[13133]: 171C17206: to=<recipient(a)dest.examle.org>, relay=dovecot, delay=0.17, delays=0.1/0/0/0.07, dsn=5.3.0, status=bounced (Command died with status 89: "/usr/lib/dovecot/deliver". Command output: doveconf: Fatal: Error in configuration file /etc/dovecot/certs.conf line 3: key_file: open(/etc/ssl/private/ssl-cert-snakeoil.key) failed: Permission denied ) How can I solve this (short of making the private key file world readable, of course)? Regards mks I have this in Postfix' master.cf: > dovecot unix - n n - - pipe > flags=DROhu user=vmail:vmail argv=/usr/lib/dovecot/deliver -e -f ${sender} -a ${recipient} -d ${user}@${domain} # LANG=C id vmail uid=501(vmail) gid=501(vmail) groups=501(vmail),104(ssl-cert) # LANG=C ls -l /etc/ssl/private/ total 4 -rw-r----- 1 root ssl-cert 1704 Feb 4 17:15 ssl-cert-snakeoil.key # doveconf -n # 2.4.2-2+debian13 (0962ed2104): /etc/dovecot/dovecot.conf # Pigeonhole version 2.4.2-2+debian13 (767418c3) # OS: Linux 6.19.0-2-MANJARO x86_64 Debian 13.3 btrfs # Hostname: debian13-cont dovecot_config_version = 2.4.2 dovecot_storage_version = 2.4.2 log_debug = category=sql mail_driver = sdbox mail_gid = vmail mail_home = /var/spool/vmail/home/%{user | domain}/%{user | username} mail_path = /var/spool/vmail/mail/%{user | domain}/%{user | username} mail_plugins { quota = yes } mail_uid = vmail protocols = imap lmtp sieve sql_driver = mysql mysql localhost { dbname = postfixadmin password = # hidden, use -P to show it user = postfixadmin } passdb sql { query = SELECT 'vmail' AS userdb_uid, 'vmail' AS userdb_gid, CONCAT('/var/spool/vmail/home/', maildir) AS userdb_home, CONCAT(quota, 'B') AS userdb_quota_storage_size, username AS user, password FROM mailbox WHERE username = '%{user}' AND active = '1'; } userdb prefetch { } userdb sql { iterate_query = SELECT username AS user FROM mailbox WHERE active = '1'; query = SELECT 'vmail' AS uid, 'vmail' AS gid, CONCAT('/var/spool/vmail/home/', maildir) AS home, CONCAT(quota, 'B') AS quota_storage_size, username AS user, password FROM mailbox WHERE username = '%{user}' AND active = '1'; } namespace inbox { inbox = yes separator = / mailbox Drafts { special_use = "\\Drafts" } mailbox Entwürfe { special_use = "\\Drafts" } mailbox Junk { special_use = "\\Junk" } mailbox Trash { special_use = "\\Trash" } mailbox "Gelöschte Objekte" { special_use = "\\Trash" } mailbox Sent { special_use = "\\Sent" } mailbox "Gesendete Objekte" { special_use = "\\Sent" } } service auth { inet_listener tcp_auth { port = 12345 } unix_listener /var/spool/postfix/private/auth { group = postfix mode = 0666 user = postfix } } service auth-worker { } ssl_server { cert_file = /etc/ssl/certs/ssl-cert-snakeoil.pem key_file = /etc/ssl/private/ssl-cert-snakeoil.key } protocol imap { mail_plugins { imap_quota = yes } } quota "User quota" { } dict_server { dict mysql { driver = sql sql_driver = mysql dict_map priv/quota/messages { sql_table = quota username_field = username dict_map_value_field messages { } } dict_map priv/quota/storage { sql_table = quota username_field = username dict_map_value_field bytes { } } } } quota_clone { dict proxy { name = mysql } }

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dovecot 2.4 changes
by Curtis J Blank 18 Feb '26

18 Feb '26

I just did a Tumbleweed upgrade. then I had to fix dovecot. No warning that dovecot was going to break what so ever. Below is all the things I had to fix. And then I could not read my email in Thunderbird because you changed: mail_location = mbox:~/mail:INBOX=/var/spool/mail/%u to mail_driver = mbox mail_path = ~/mail mail_inbox_path = /var/spool/mail/%{user} and the "%u" to "%{user}" was the showstopper. What a crock of BS! I spent 3 hours determining the problem and then fixing dovecot because you decided to make major changes for no good reason. It worked just fine the way it was. You could have automated the changes by providing a utility that would make the changes the first time it started up after the upgrade. I had to try to start dovecot and when it failed to start look in the log and see the error and fix it. Over and over and over and over and over and over and over and... Like I said what a bunch of BS! Yes this is a rant. And maybe openSuSE's is too blame also. Jan 24 03:33:35 server dovecot[2223449]: doveconf: Fatal: Error in configuration file /etc/dovecot/dovecot.conf line 25: The first setting must be dovecot_config_version Jan 24 03:36:45 server dovecot[4626]: doveconf: Fatal: Error in configuration file /etc/dovecot/dovecot.conf line 25: The first setting must be dovecot_config_version Jan 24 03:46:10 server dovecot[21464]: doveconf: Fatal: Error in configuration file /etc/dovecot/dovecot.conf line 2: Invalid dovecot_config_version: Currently supported versions are: 2.4.0 2.4.1 2.4.2 Jan 24 03:48:45 server dovecot[22135]: doveconf: Fatal: Error in configuration file /etc/dovecot/dovecot.conf line 92: dict { } is missing section name Jan 24 03:51:47 server dovecot[28824]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/auth-system.conf.ext line 10: passdb { } is missing section name Jan 24 03:53:22 server dovecot[29258]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/auth-system.conf.ext line 10: passdb { } is missing section name Jan 24 03:55:26 server dovecot[29906]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/auth-system.conf.ext line 49: userdb { } is missing section name Jan 24 03:56:57 server dovecot[30179]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/10-director.conf line 40: inet_listener { } is missing section name Jan 24 03:58:37 server dovecot[30652]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/10-logging.conf line 64: Unknown section name: plugin Jan 24 04:01:32 server dovecot[37805]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/10-mail.conf line 31: mail_location: Unknown setting: mail_location Jan 24 04:05:30 server dovecot[38898]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/10-mail.conf line 32: mail_location: Unknown setting: mail_location Jan 24 04:06:35 server dovecot[39158]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/10-ssl.conf line 23: ssl_cert: Unknown setting: ssl_cert Jan 24 04:09:07 server dovecot[39707]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/10-ssl.conf line 25: ssl_server_cert_file: open(/etc/dovecot/conf.d/-----BEGIN CERTIFICATE----- Jan 24 04:09:07 server dovecot[39707]: doveconf: Fatal: -----END CERTIFICATE----- Jan 24 04:09:07 server dovecot[39707]: doveconf: Fatal: ) failed: File name too long Jan 24 04:14:52 server dovecot[47156]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/10-ssl.conf line 27: ssl_server_cert_file: open(/etc/dovecot/conf.d/-----BEGIN CERTIFICATE----- Jan 24 04:14:52 server dovecot[47156]: doveconf: Fatal: -----END CERTIFICATE----- Jan 24 04:14:52 server dovecot[47156]: doveconf: Fatal: ) failed: File name too long Jan 24 04:17:35 server dovecot[54187]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/10-ssl.conf line 72: ssl_dh: Unknown setting: ssl_dh Jan 24 04:19:04 server dovecot[54532]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/10-ssl.conf line 93: ssl_prefer_server_ciphers: Unknown setting: ssl_prefer_server_ciphers Jan 24 04:21:07 server dovecot[60961]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/90-acl.conf line 11: Unknown section name: plugin Jan 24 04:22:40 server dovecot[61409]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/90-acl.conf line 17: Unknown section name: plugin Jan 24 04:23:35 server dovecot[61624]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/90-plugin.conf line 9: Unknown section name: plugin Jan 24 04:24:40 server dovecot[61932]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/90-quota.conf line 17: Unknown section name: plugin Jan 24 04:25:38 server dovecot[62301]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/90-quota.conf line 41: Unknown section name: plugin Jan 24 04:26:12 server dovecot[62335]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/90-quota.conf line 69: Unknown section name: plugin Jan 24 04:26:42 server dovecot[62550]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/90-quota.conf line 78: Unknown section name: plugin Jan 24 04:27:05 server dovecot[62582]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/90-sieve-extprograms.conf line 9: Unknown section name: plugin Jan 24 04:28:11 server dovecot[62819]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/90-sieve.conf line 24: Unknown section name: plugin Jan 24 04:29:02 server dovecot[63099]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/90-sieve.conf line 39: sieve: Unknown setting: sieve Jan 24 04:36:01 server dovecot[71295]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/90-sieve.conf line 39: sieve: Unknown setting: sieve Jan 24 04:39:04 server dovecot[72067]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/90-sieve.conf line 40: sieve: Unknown setting: sieve (sieve_script_sieve or sieve_script_personal_sieve not found either.) Jan 24 04:47:39 server dovecot[86665]: doveconf: Fatal: Error in configuration file /etc/dovecot/dovecot.conf: ssl_options: unknown flag: 'no_compression' Jan 24 04:50:51 server dovecot[93375]: doveconf: Fatal: dovecot_storage_version setting must be set Jan 24 05:01:51 server dovecot[105836]: doveconf: Fatal: Error in configuration file /etc/dovecot/conf.d/10-mail.conf line 31: mail_location: Unknown setting: mail_location Jan 24 05:06:18 cjbnew dovecot: imap(bob)<107288><SOtYQyBJTOXAqBTz>: Error: Mailbox INBOX: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:0 mode=0755) Jan 24 05:06:18 cjbnew dovecot: imap(bob)<107288><SOtYQyBJTOXAqBTz>: Error: Mailbox INBOX: Failed to autocreate mailbox: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:0 mode=0755) Jan 24 05:06:18 cjbnew dovecot: imap(bob)<107289><9+pYQyBJTeXAqBTz>: Error: Mailbox INBOX: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:0 mode=0755) Jan 24 05:06:18 cjbnew dovecot: imap(bob)<10Jan 24 05:06:18 cjbnew dovecot: imap(bob)<107288><SOtYQyBJTOXAqBTz>: Error: Mailbox INBOX: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:0 mode=0755) Jan 24 05:06:18 cjbnew dovecot: imap(bob)<107288><SOtYQyBJTOXAqBTz>: Error: Mailbox INBOX: Failed to autocreate mailbox: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:0 mode=0755) Jan 24 05:06:18 cjbnew dovecot: imap(bob)<107289><9+pYQyBJTeXAqBTz>: Error: Mailbox INBOX: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:0 mode=0755) Jan 24 05:06:18 cjbnew dovecot: imap(bob)<107289><9+pYQyBJTeXAqBTz>: Error: Mailbox INBOX: Failed to autocreate mailbox: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:0 mode=07557289><9+pYQyBJTeXAqBTz>: Error: Mailbox INBOX: Failed to autocreate mailbox: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:0 mode=0755) Jan 24 05:08:38 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:0 mode=0755) Jan 24 05:08:38 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: Failed to autocreate mailbox: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:0 mode=0755) Jan 24 05:11:10 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:0 mode=0755) Jan 24 05:11:10 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: Failed to autocreate mailbox: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:0 mode=0755) Jan 24 05:15:09 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:473 mode=0755) Jan 24 05:15:09 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: Failed to autocreate mailbox: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, dir owned by 0:473 mode=0755) Jan 24 05:18:35 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, we're not in group 473(mail), dir owned by 0:473 mode=0775) Jan 24 05:18:35 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: Failed to autocreate mailbox: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, we're not in group 473(mail), dir owned by 0:473 mode=0775) Jan 24 05:19:09 cjbnew dovecot: imap(bob)<122933></apLcSBJaKrAqBTq>: Disconnected: Connection closed (SELECT finished 0.138 secs ago) in=102 out=787 deleted=0 expunged=0 trashed=0 hdr_count=0 hdr_bytes=0 body_count=0 body_bytes=0 Jan 24 05:19:58 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, we're not in group 473(mail), dir owned by 0:473 mode=0775) Jan 24 05:19:58 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: Failed to autocreate mailbox: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, we're not in group 473(mail), dir owned by 0:473 mode=0775) Jan 24 05:20:20 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, we're not in group 473(mail), dir owned by 0:473 mode=0775) Jan 24 05:20:20 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: Failed to autocreate mailbox: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, we're not in group 473(mail), dir owned by 0:473 mode=0775) Jan 24 05:21:17 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, we're not in group 473(mail), dir owned by 0:473 mode=0775) Jan 24 05:21:17 cjbnew dovecot: imap(bob)<107806><1/QbSyBJUOXAqBTz>: Error: Mailbox INBOX: Failed to autocreate mailbox: open(/var/spool/mail/%u) failed: Permission denied (euid=500(bob) egid=100(users) missing +w perm: /var/spool/mail, we're not in group 473(mail), dir owned by 0:473 mode=0775)

12 19

"Synchronization corrupted index header" with mdbox: thousands of deleted e-mails reappeared in INBOX
by Ákos Szőts 17 Feb '26

17 Feb '26

Hi everyone, Suddenly, the following messages appeared in my Dovecot error log: master: Warning: Killed with signal 15 (by pid=0 uid=0 code=kill) Error: Mailbox Trash: Synchronization corrupted index header [...]/Trash/dbox-Mails/dovecot.index: uidvalidity=0, but next_uid=73 Warning: Mailbox Trash: fscking index file [...]/Trash/dbox-Mails/dovecot.index Warning: mdbox([...]/mail/storage): rebuilding indexes: Mailbox Trash index was fsck'd Warning: mdbox([...]/mail/storage): fscking index file [...]/index/inbox/storage/dovecot.map.index Error: Mailbox INBOX: [...]/INBOX/dbox-Mails/dovecot.index reset, view is now inconsistent The first message is because I restarted the container. Since then, Thunderbird shows thousands of previously deleted e-mails again in INBOX where all my messages are marked as unread. - Do you know what can cause it and how can I avoid to happen again? - Is the used mdbox storage engine that fragile? Is the fault tolerance of other engines better? I have a backup from some days ago. Is it possible to somehow revert back to it and sync the new e-mails on top of those? Version: 2.4.2. Thank you, Ákos

2 1

Most relevant documents for 2.4.x config file syntax
by Steve Litt 16 Feb '26

16 Feb '26

Hi all, Some time has gone by, so I'm hoping there's some good documentation for somebody needing syntax help on building a 2.4.x Dovecot. I've seen https://doc.dovecot.org/2.4.0/installation/upgrade/2.3-to-2.4.html , but it's not useful to me because I don't know *where* all those various pieces go. Which things go in what curly braces? It doesn't say. https://doc.dovecot.org/2.4.2/core/config/quick.html looks like an excellent starting place. Do you agree? What other *simple* documentation do you recommend? Because I am not and never was a Dovecot expert, I'll need something that does a considerable amount of teaching: A sort of Dovecot 4.2 For Dummies type thing. Thanks, SteveT Steve Litt http://444domains.com

3 4

Configuration upgrade tool
by Aki Tuomi 15 Feb '26

15 Feb '26

Hi! To make migrating from Dovecot 2.3 to 2.4 a bit easier, we are now providing a tool that helps upgrade your existing configuration. The tool allows you to upload either a full dovecot.conf or selected ancillary configuration files from a 2.3 setup, and will attempt to convert them accordingly. You can find the tool here: https://dovecot.org/upgrader/ We do not store any of the configurations processed by the tool, nor do we track who uses it. It's offered as-is, without any warranty or guarantee. If you run into any issues, unexpected results, or have feedback about the tool, please let us know — it’s very much appreciated. Please note that the tool can make mistakes, so we strongly recommend carefully reviewing and testing the output before using it in production. There are currently no plans to release this tool as open source. Regards, Aki Tuomi Open-Xchange oy

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Sdbox/mdbox purge on Public folders
by luke+dovecot＠psy.io 15 Feb '26

15 Feb '26

Hi dovecot mailing list people, After having looked through the mailing list archives, tried various search engines & asked an LLM to hallucinate an answer all to no avail, I now pose the following question to you all: For a Dovecot 2.4 system that uses mail_driver = mdbox for regular mailboxes and also has a public namespace, how might I invoke the maintenance routine of `doveadm purge` against the m.1, m.2 ... m.N files under the mail_path location? Below is the snippet of what I have in the configuration files for the public namespace: namespace public { type = public separator = / prefix = Public/ mail_path = /var/spool/mail/Public mail_index_private_path = ~/public subscriptions = yes mailbox "communal" { auto = subscribe } } Since my dovecot instance is a self-hosted matter, I am in a position to move all mail data out of there, delete any left over storage files and change the mail_driver to Maildir, if that is the easiest way to manage the risk of dbox m file sprawl/growth. Best regards, Luke

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Is there a lint utility for 2.4.x configuration?
by Steve Litt 14 Feb '26

14 Feb '26

Hi all, I use a local Dovecot IMAP server to store all my emails, which I access from either Claws-Mail or Evolution. On 7/7/2025 my email stopped working, a few hours of troubleshooting led to a Dovecot problem, a few more hours led to the 2.3 to 2.4 config file changes, and the next 3 days I went without email while trying to get a working 2.4. Finally I managed to downgrade back to 2.3.x and restore the config from backup, and didn't lose too many emails. I've waited 6 months for all the dust to settle, and now I'm going to try to make a test VM (Void Linux) with 2.4.x, using phony baloney data because I don't want to lose my email capabilities again. So my first question is this: Is there a lint utility for my configuration, so that I can cut down on experimenting with 50 different variables at once and reading conflicting documentation? Here's what I know so far about lint utilities: * I know doveconf -n and dovecot -n dump non-default settings, but I don't think they can detect syntax errors. * dovecot-sysreport doesn't seem to give me info about syntax errors. * None of the doveadm commands seem to check syntax. Thanks, SteveT Steve Litt http://444domains.com

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