Since the update (20.11.) I can't send any attachments (size doesn't matter) - Outlook stuck at sending and in the log there's only:
[2023-11-22 01:40:28.933509]: exmdb_client: HX_inet_connect to [::1]:5000: Connection refused
[2023-11-22 01:40:39.839847]: exmdb_client: protocol error connecting to [::1]:5000//var/lib/gromox/user/
[2023-11-22 01:40:58.574293]: exmdb_client: protocol error connecting to [::1]:5000//var/lib/gromox/user/
[2023-11-22 01:45:39.209555]: exmdb_client: HX_inet_connect to [::1]:5000: Connection reset by peer
[2023-11-22 01:45:39.209972]: exmdb_client: protocol error connecting to [::1]:5000//var/lib/gromox/user/
[2023-11-22 01:52:37.566663]: exmdb_client: HX_inet_connect to [::1]:5000: Connection refused
[2023-11-22 01:54:16.306434]: exmdb_client: HX_inet_connect to [::1]:5000: Connection reset by peer
[2023-11-22 01:59:43.320951]: exmdb_client: HX_inet_connect to [::1]:5000: Connection refused
EDIT
Just in Online Version - Cached is everything fine...
This is the error from the nginx-mapi-error.log
2023/11/22 02:17:36 [error] 2199#2199: *1964 upstream prematurely closed connection while reading response header from upstream, client: 192.168.2.250, server: _, request: "POST /mapi/emsmdb/?MailboxId=696e666f-4069-742d-6869-617309000000@maildomain.de HTTP/1.1", upstream: "https://[::1]:10443/mapi/emsmdb/?MailboxId=696e666f-4069-742d-6869-617309000000@maildomain.de", host: "grommunio.maildomain.de"
2023/11/22 02:17:36 [error] 2199#2199: *114 upstream prematurely closed connection while reading upstream, client: 192.168.2.250, server: _, request: "POST /mapi/emsmdb/?MailboxId=6d617474-6869-6173-2e6d-696c01000000@maildomain.de HTTP/1.1", upstream: "https://[::1]:10443/mapi/emsmdb/?MailboxId=6d617474-6869-6173-2e6d-696c01000000@maildomain.de", host: "grommunio.maildomain.de"
2023/11/22 02:17:36 [error] 2199#2199: *30 upstream prematurely closed connection while reading upstream, client: 192.168.2.250, server: _, request: "POST /mapi/emsmdb/?MailboxId=696e666f-4069-742d-6869-617309000000@maildomain.de HTTP/1.1", upstream: "https://[::1]:10443/mapi/emsmdb/?MailboxId=696e666f-4069-742d-6869-617309000000@maildomain.de", host: "grommunio.maildomain.de"
2023/11/22 02:17:37 [error] 2199#2199: *1972 no live upstreams while connecting to upstream, client: 192.168.2.250, server: _, request: "POST /mapi/emsmdb/?MailboxId=696e666f-4069-742d-6869-617309000000@maildomain.de HTTP/1.1", upstream: "https://gromoxhttp/mapi/emsmdb/?MailboxId=696e666f-4069-742d-6869-617309000000@maildomain.de", host: "grommunio.maildomain.de"