Running “kmail --view ‹filename›” from the command line results in the following message dialog: Error — KMail The file or folder file:‹filename› does not exist. After clicking Ok, kmail terminates with return value 0. Reproducible: Always Console output of “kmail --version”: kmail2 5.0.3 Console output of “kmail --view mail.mbox”: log_kontactinterface: kontact not running -- start standalone application log_kmail: log_kmail: Delaying instance creation. log_kmail: Starting up... "KMail Kernel ETM" () connectToServer "/tmp/akonadi-toni.fYWxag/akonadiserver.socket" "" connectToServer "/tmp/akonadi-toni.fYWxag/akonadiserver.socket" "/subscriber/kmail2_4635_C4261z" connectToServer "/tmp/akonadi-toni.fYWxag/akonadiserver.socket" log_mailtransport: Have SMTP, Sendmail, and 0 Akonadi types. log_mailtransport: "736633453" log_mailtransport: type 0 log_mailtransport: "125577346" log_mailtransport: type 0 log_mailtransport: Pass a valid window to KWallet::Wallet::openWallet(). log_kmail: log_kmail: KMail init with akonadi server state: 2 log_mailcommon: Initialized and looking for specialcollection folders. "/subscriber/kmail2_4635_2ZQ5rA" connectToServer "/tmp/akonadi-toni.fYWxag/akonadiserver.socket" log_kmail: log_kmail: url : QUrl("file:file:mail.mbox") done org.kde.akonadi.ETM: GEN true false false org.kde.akonadi.ETM: collection: QVector() org.kde.akonadi.ETM: Connected to "Akonadi" , using protocol version 51 Server says: "Not Really IMAP server" Connected to "Akonadi" , using protocol version 51 Server says: "Not Really IMAP server" Connected to "Akonadi" , using protocol version 51 Server says: "Not Really IMAP server" Connected to "Akonadi" , using protocol version 51 Server says: "Not Really IMAP server" log_mailtransport: Read defaultResourceId "akonadi_maildir_resource_0" from config. Found resource "akonadi_maildir_resource_0" org.kde.akonadi.ETM: Subtree: 3 QSet(3, 9, 8, 11, 4, 7, 6) org.kde.akonadi.ETM: Subtree: 15 QSet(20, 23, 22, 17, 44, 16, 19, 18, 41, 40, 43, 15, 42, 37, 36, 39, 38, 33, 32, 35, 34, 121, 122, 29, 28, 31, 30, 25, 24, 27, 26, 21) org.kde.akonadi.ETM: Subtree: 103 QSet(111, 110, 105, 104, 107, 106, 117, 103, 116, 118, 113, 112, 115, 114, 109, 108) org.kde.akonadi.ETM: Subtree: 1 QSet(126, 120, 123, 1) org.kde.akonadi.ETM: Fetch job took 62 msec org.kde.akonadi.ETM: was collection fetch job: collections: 59 org.kde.akonadi.ETM: first fetched collection: "Search" Fetched 7 collections. Fetched root collection 3 and 7 local folders (total 7 collections). resourceId "akonadi_maildir_resource_0" All done! Comitting. Emitting changed for "akonadi_maildir_resource_0" Emitting defaultFoldersChanged. org.kde.akonadi.ETM: Fetch job took 76 msec org.kde.akonadi.ETM: was collection fetch job: collections: 11 org.kde.akonadi.ETM: first fetched collection: "Search" Emitting changed for "akonadi_imap_resource_1" Emitting changed for "akonadi_imap_resource_3" log_kmail: log_pimcommon: ~StorageServiceJobConfigPrivate log_mailcommon: log_mailcommon: