Desktop app disconnects on trying to add a "second device" [how does LAN pairing work]

Delta Chat disconnects abruptly right before generating a QR-code for adding another device, then goes back online after quitting that section. Needless to say, logging in with the QR-code fails. This happens to every profile, regardless of what relay I use.

This is how it looks like:
Aug-14-2026 00-01-02

And this are the logs, the event is somewhere in there I hope:
DC Desktop Version: 2.57.0 (git: v2.57.0-prepare-release-2.57.0)
Core Version: v2.57.0
Runtime: ElectronRuntime

[Versions]
electron=42.5.0
node=24.17.0
SQLite=3.46.1

[Runtime Info]
isMac=true
isAppx=false
target=electron
runningUnderARM64Translation=false
rpcServerPath=/Applications/DeltaChat.app/Contents/Resources/app.asar.unpacked/node_modules/@deltachat/stdio-rpc-server-darwin-x64/deltachat-rpc-server
isContentProtectionSupported=true
buildTimestamp=1785046889999

[Chatmail Core Info | About Current Profile]
Selected Profile ID: 37
arch=64
bcc_self=1
blobdir=/Users/amplebug/Library/Containers/chat.delta.desktop.electron/Data/Library/Application Support/DeltaChat/accounts/6ea546fb-5efb-48df-9774-71a8645a249a/dc.db-blobs
bot=0
database_dir=/Users/amplebug/Library/Containers/chat.delta.desktop.electron/Data/Library/Application Support/DeltaChat/accounts/6ea546fb-5efb-48df-9774-71a8645a249a/dc.db
database_encrypted=false
database_version=159
debug_assertions=Off
debug_logging=0
delete_device_after=0
deltachat_core_version=v2.57.0
disable_idle=false
donation_request_next_check=0
download_limit=0
first_key_contacts_msg_id=
fix_is_chatmail=false
force_encryption=true
gossip_period=172800
imap_server_id={"name": "Dovecot"}
is_chatmail=true
is_muted=false
journal_mode=wal
last_cant_decrypt_outgoing_msgs=0
last_housekeeping=1786698402
last_msg_id=11
level=awesome
mdns_enabled=1
media_quality=0
messages_in_contact_requests=0
num_cpus=4
number_of_chat_messages=2
number_of_chats=2
number_of_contacts=0
private_key_count=1
private_tag=<unset>
proxy_enabled=0
public_key_count=0
selfavatar=<unset>
sqlite_version=3.46.1
stats_id=<unset>
stats_last_sent=0
stats_sending=false
std_header_protection_composing=
sync_msgs=1
team_profile=false
test_hooks=
uptime=0h 0m 23s
used_transport_settings=1: ***@deltachat.kz imap:[deltachat.kz:993:tls, deltachat.kz:143:starttls, deltachat.kz:443:tls] smtp:[deltachat.kz:465:tls, deltachat.kz:587:starttls, deltachat.kz:443:tls] cert_strict
webxdc_realtime_enabled=true
who_can_call_me=1

Storage Usage:
[Blob Directory Size]: 129.94 KiB
[Database Size]: 472 KiB
[Largest Tables]:
   transports:               4 KiB,      1 rows
   tokens:                   4 KiB,      0 rows
   tls_spki:                 4 KiB,      1 rows
   stats_sending_enabled_events:      4 KiB,      0 rows
   stats_sending_disabled_events:      4 KiB,      0 rows
   stats_securejoin_uipaths:      4 KiB,      0 rows
   stats_securejoin_sources:      4 KiB,      0 rows
   stats_securejoin_invites:      4 KiB,      0 rows
   stats_msgs:               4 KiB,      0 rows
   sqlite_sequence:          4 KiB,      9 rows
[Webxdc With Biggest Status Update Space Usage]:

[Log]
2026-08-14T09:06:30.382Z	main/index            	INFO	""	"Deltachat Version 2.57.0 v2.57.0-prepare-release-2.57.0 1785046889999"
2026-08-14T09:06:30.743Z	main/index            	INFO	""	"cwd /Users/amplebug/Library/Containers/chat.delta.desktop.electron/Data/Library/Application Support/DeltaChat/accounts"
2026-08-14T09:06:30.786Z	main/deltachat        	INFO	""	"using deltachat-rpc-server at"	{"serverPath":"/Applications/DeltaChat.app/Contents/Resources/app.asar.unpacked/node_modules/@deltachat/stdio-rpc-server-darwin-x64/deltachat-rpc-server"}
2026-08-14T09:06:30.795Z	main/deltachat        	INFO	""	"HI"
2026-08-14T09:06:31.022Z	main/menu             	INFO	""	"rebuilding menu with locale fr"
2026-08-14T09:06:31.032Z	main/cleanup_temp_dir 	INFO	""	"Deleted 0 internal tmp directories"
2026-08-14T09:06:31.306Z	logger/log-cleanup    	INFO	""	"Successfuly deleted 1 old logfiles"
2026-08-14T09:06:32.767Z	/mainWindow           	INFO	""	"preq"	"media"
2026-08-14T09:06:32.801Z	main/menu             	INFO	""	"rebuilding menu with locale fr"
2026-08-14T09:06:32.985Z	renderer/stockstrings 	INFO	""	"loading core translations"
2026-08-14T09:06:33.016Z	core/event            	INFO	""	37	"src/key.rs:133: Converting secret key to public key."
2026-08-14T09:06:33.127Z	core/event            	INFO	""	19	"src/key.rs:133: Converting secret key to public key."
2026-08-14T09:06:33.200Z	core/event            	INFO	""	27	"src/key.rs:133: Converting secret key to public key."
2026-08-14T09:06:33.201Z	core/event            	INFO	""	30	"src/key.rs:133: Converting secret key to public key."
2026-08-14T09:06:33.201Z	core/event            	INFO	""	36	"src/key.rs:133: Converting secret key to public key."
2026-08-14T09:06:33.201Z	core/event            	INFO	""	28	"src/key.rs:133: Converting secret key to public key."
2026-08-14T09:06:33.201Z	core/event            	INFO	""	25	"src/key.rs:133: Converting secret key to public key."
2026-08-14T09:06:33.201Z	core/event            	INFO	""	34	"src/key.rs:133: Converting secret key to public key."
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/scheduler.rs:68: starting IO"
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/scheduler.rs:347: Starting inbox loop."
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/scheduler.rs:367: Transport 1: Preparing new IMAP session for inbox."
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/imap.rs:316: Connecting to IMAP server."
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/scheduler.rs:541: Starting SMTP loop."
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/scheduler.rs:698: scheduler is running"
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/contact.rs:2158: Recently seen loop waiting for 24h 0m 0s or interrupt"
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/location.rs:731: Location loop is waiting for 24h 0m 0s or interrupt"
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/ephemeral.rs:614: Ephemeral loop waiting for deletion in 24h 0m 0s or interrupt"
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/imap.rs:331: IMAP trying to connect to deltachat.kz:993:tls."
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/net/dns.rs:140: No memory-cached DNS resolution for deltachat.kz available, waiting for the resolver."
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/net/dns.rs:180: Resolved deltachat.kz into 85.202.192.120."
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/imap/client.rs:134: Attempting IMAP connection to deltachat.kz (85.202.192.120:993)."
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/smtp.rs:538: Selected rows from SMTP queue: []."
2026-08-14T09:06:33.268Z	core/event            	INFO	""	37	"src/smtp.rs:655: Sending MDNs."
2026-08-14T09:06:33.269Z	core/event            	INFO	""	37	"src/scheduler.rs:581: SMTP fake idle started."
2026-08-14T09:06:33.269Z	core/event            	INFO	""	37	"src/scheduler.rs:609: SMTP has no messages to retry, waiting for interrupt."
2026-08-14T09:06:33.622Z	core/event            	INFO	""	37	"src/imap.rs:356: Logging into IMAP server with LOGIN."
2026-08-14T09:06:33.762Z	core/event            	INFO	""	19	"src/chat.rs:4832: Device-message changelog-version-2.3.0 already added."
2026-08-14T09:06:33.829Z	core/event            	INFO	""	34	"src/chat.rs:4832: Device-message changelog-version-2.3.0 already added."
2026-08-14T09:06:33.841Z	core/event            	INFO	""	28	"src/chat.rs:4832: Device-message changelog-version-2.3.0 already added."
2026-08-14T09:06:33.986Z	core/event            	INFO	""	37	"src/imap.rs:416: Successfully logged into IMAP server."
2026-08-14T09:06:33.986Z	core/event            	INFO	""	37	"src/scheduler.rs:380: Transport 1: Prepared new IMAP session for inbox."
2026-08-14T09:06:33.986Z	core/event            	INFO	""	37	"src/quota.rs:88: Transport 1: Updating quota."
2026-08-14T09:06:33.998Z	core/event            	INFO	""	37	"src/message.rs:1868: Seen message Msg#11."
2026-08-14T09:06:33.998Z	core/event            	INFO	""	30	"src/chat.rs:4832: Device-message changelog-version-2.3.0 already added."
2026-08-14T09:06:34.006Z	core/event            	INFO	""	25	"src/chat.rs:4832: Device-message changelog-version-2.3.0 already added."
2026-08-14T09:06:34.014Z	core/event            	INFO	""	27	"src/chat.rs:4832: Device-message changelog-version-2.3.0 already added."
2026-08-14T09:06:34.016Z	core/event            	INFO	""	36	"src/chat.rs:4832: Device-message changelog-version-2.3.0 already added."
2026-08-14T09:06:34.020Z	core/event            	INFO	""	37	"src/chat.rs:4832: Device-message changelog-version-2.3.0 already added."
2026-08-14T09:06:34.044Z	core/event            	INFO	""	37	"src/quota.rs:106: Transport 1: Updated quota."
2026-08-14T09:06:34.045Z	core/event            	INFO	""	37	"src/imap.rs:1378: Server supports metadata, retrieving server comment and admin contact."
2026-08-14T09:06:34.298Z	core/event            	INFO	""	37	"src/imap/select_folder.rs:78: Transport 1: Selected folder \"INBOX\"."
2026-08-14T09:06:34.307Z	core/event            	INFO	""	37	"src/imap.rs:541: Transport 1: No new emails in folder \"INBOX\"."
2026-08-14T09:06:34.308Z	core/event            	INFO	""	37	"src/imap/idle.rs:47: Transport 1: Skip IDLE in \"INBOX\" because we got interrupt."
2026-08-14T09:06:34.310Z	core/event            	INFO	""	37	"src/imap.rs:541: Transport 1: No new emails in folder \"INBOX\"."
2026-08-14T09:06:34.434Z	core/event            	INFO	""	37	"src/imap/idle.rs:67: Transport 1: IDLE entering wait-on-remote state in folder \"INBOX\"."
2026-08-14T09:06:42.692Z	core/event            	INFO	""	37	"src/scheduler.rs:109: stopping IO"
2026-08-14T09:06:42.693Z	core/event            	INFO	""	37	"src/scheduler.rs:620: Shutting down SMTP loop."
2026-08-14T09:06:42.693Z	core/event            	INFO	""	37	"src/scheduler.rs:404: Transport 1: Shutting down inbox loop."
2026-08-14T09:06:42.693Z	core/event            	INFO	""	37	"src/imap/idle.rs:81: \"INBOX\": Received interrupt, stopping IDLE."
2026-08-14T09:06:42.695Z	core/event            	INFO	""	37	"src/sql.rs:990: Start housekeeping..."
2026-08-14T09:06:42.696Z	core/event            	INFO	""	37	"src/sql.rs:1051: 4 files in use."
2026-08-14T09:06:42.697Z	core/event            	INFO	""	37	"src/sql.rs:775: Incremental vacuum freed 0 pages."
2026-08-14T09:06:42.703Z	core/event            	INFO	""	37	"src/sql.rs:682: wal_checkpoint: Total time: 5.127ms. Writers blocked for: 1.342ms. Readers blocked for: 1.177ms."
2026-08-14T09:06:42.705Z	core/event            	INFO	""	37	"src/sql.rs:921: Housekeeping done."
2026-08-14T09:06:49.518Z	core/event            	INFO	""	37	"src/context.rs:810: Signaling the ongoing process to stop ASAP."
2026-08-14T09:06:49.557Z	core/event            	INFO	""	37	"src/imex/transfer.rs:268: Backup transfer canceled by the user, stopping accept loop."
2026-08-14T09:06:49.557Z	core/event            	INFO	""	37	"src/imex/transfer.rs:153: Finished accept loop."
2026-08-14T09:06:49.557Z	core/event            	INFO	""	37	"src/context.rs:797: Ongoing stopped in 28.938ms"
2026-08-14T09:06:49.557Z	core/event            	INFO	""	37	"src/scheduler.rs:68: starting IO"
2026-08-14T09:06:49.566Z	core/event            	INFO	""	37	"src/context.rs:816: No ongoing process to stop."
2026-08-14T09:06:49.567Z	core/event            	INFO	""	37	"src/context.rs:816: No ongoing process to stop."
2026-08-14T09:06:49.568Z	core/event            	INFO	""	37	"src/scheduler.rs:541: Starting SMTP loop."
2026-08-14T09:06:49.568Z	core/event            	INFO	""	37	"src/scheduler.rs:347: Starting inbox loop."
2026-08-14T09:06:49.568Z	core/event            	INFO	""	37	"src/scheduler.rs:367: Transport 1: Preparing new IMAP session for inbox."
2026-08-14T09:06:49.568Z	core/event            	INFO	""	37	"src/imap.rs:316: Connecting to IMAP server."
2026-08-14T09:06:49.568Z	core/event            	INFO	""	37	"src/scheduler.rs:698: scheduler is running"
2026-08-14T09:06:49.572Z	core/event            	INFO	""	37	"src/ephemeral.rs:614: Ephemeral loop waiting for deletion in 24h 0m 0s or interrupt"
2026-08-14T09:06:49.573Z	core/event            	INFO	""	37	"src/contact.rs:2158: Recently seen loop waiting for 24h 0m 0s or interrupt"
2026-08-14T09:06:49.573Z	core/event            	INFO	""	37	"src/smtp.rs:538: Selected rows from SMTP queue: []."
2026-08-14T09:06:49.573Z	core/event            	INFO	""	37	"src/smtp.rs:655: Sending MDNs."
2026-08-14T09:06:49.573Z	core/event            	INFO	""	37	"src/imap.rs:331: IMAP trying to connect to deltachat.kz:993:tls."
2026-08-14T09:06:49.573Z	core/event            	INFO	""	37	"src/net/dns.rs:134: Using memory-cached DNS resolution for deltachat.kz."
2026-08-14T09:06:49.573Z	core/event            	INFO	""	37	"src/net/dns.rs:180: Resolved deltachat.kz into 85.202.192.120."
2026-08-14T09:06:49.573Z	core/event            	INFO	""	37	"src/scheduler.rs:581: SMTP fake idle started."
2026-08-14T09:06:49.573Z	core/event            	INFO	""	37	"src/scheduler.rs:609: SMTP has no messages to retry, waiting for interrupt."
2026-08-14T09:06:49.578Z	core/event            	INFO	""	37	"src/location.rs:731: Location loop is waiting for 24h 0m 0s or interrupt"
2026-08-14T09:06:49.584Z	core/event            	INFO	""	37	"src/imap/client.rs:134: Attempting IMAP connection to deltachat.kz (85.202.192.120:993)."

For adding a new device, both devices need to be on the same LAN at the same time while the QR code is showing. It does not matter if ongoing WAN sync access to your chatmail account is temporarily halted during the pairing process.

Both devices are on the same network, yet I cannot add new device.

Receiving Error: Get backup failed: failed connecting to remote endpoint: timed out

So it’s a normal behavior for a client to disconnect specifically while adding another device? If it’s so normal, how come I’ve just encountered it? Been (successfully) adding new devices before, never saw such thing.

Thanks for the report!

The “disconnects” thing is intentional: when transferring a backup we want to make sure that the database is not modified, so we stop IO. We disconnect from the mail servers and not from the network entirely.
Although we might want to somehow better display this…

The fact that you couldn’t transfer the backup is not directly related to this “disconnected” message. It could be related to your network conditions: firewall, guest Wi-Fi, etc. See FAQ - Delta Chat.