diff --git a/plinth/modules/email/data/etc/dovecot/conf.d/90-freedombox-mailboxes.conf b/plinth/modules/email/data/etc/dovecot/conf.d/90-freedombox-mailboxes.conf
index 1456360ce..209d932b5 100644
--- a/plinth/modules/email/data/etc/dovecot/conf.d/90-freedombox-mailboxes.conf
+++ b/plinth/modules/email/data/etc/dovecot/conf.d/90-freedombox-mailboxes.conf
@@ -1,43 +1,71 @@
 # Direct edits to this file will be lost!
 # Manage your settings on FreedomBox <https://localhost/plinth/apps/email/>
 
+# Mark various mailboxes with special use flags (RFC 6154). Various names used
+# in mail clients for mailboxes: https://www.imapwiki.org/SpecialUse
+
 namespace inbox {
+  # Archive
   mailbox Archive {
     auto = subscribe
     special_use = \Archive
   }
+  mailbox Archives {  # Thunderbird
+    auto = no
+    special_use = \Archive
+  }
+
+  # Drafts
   mailbox Drafts {
     auto = subscribe
     special_use = \Drafts
   }
-  mailbox Junk {
-    auto = subscribe
-    autoexpunge = 30d
-    special_use = \Junk
-  }
-  mailbox Trash {
-    auto = subscribe
-    autoexpunge = 30d
-    special_use = \Trash
-  }
-
-  mailbox INBOX.Junk {
-    auto = no
-    autoexpunge = 30d
-    special_use = \Junk
-  }
-  mailbox INBOX.Trash {
-    auto = no
-    autoexpunge = 30d
-    special_use = \Trash
-  }
 
+  # Sent
   mailbox Sent {
     auto = subscribe
     special_use = \Sent
   }
-  mailbox "Sent Messages" {
+  mailbox "Sent Items" {  # Outlook 2010/2013
     auto = no
     special_use = \Sent
   }
+  mailbox "Sent Messages" {  # iOS
+    auto = no
+    special_use = \Sent
+  }
+
+  # Junk
+  mailbox Junk {
+    auto = subscribe
+    autoexpunge = 60d
+    special_use = \Junk
+  }
+  mailbox Spam {  # KMail, K-9 Mail
+    auto = no
+    autoexpunge = 60d
+    special_use = \Junk
+  }
+  mailbox "Junk E-mail" {  # Outlook 2010
+    auto = no
+    autoexpunge = 60d
+    special_use = \Junk
+  }
+  mailbox INBOX.Junk {
+    auto = no
+    autoexpunge = 60d
+    special_use = \Junk
+  }
+
+  # Trash
+  mailbox Trash {
+    auto = subscribe
+    autoexpunge = 60d
+    special_use = \Trash
+  }
+  mailbox INBOX.Trash {
+    auto = no
+    autoexpunge = 60d
+    special_use = \Trash
+  }
 }