Problem is solved! Decsription is updated.
The Basics
- Nextcloud Server version (e.g., 29.x.x):
- 35.0.2
- Nextcloud Files version (e.g., 29.x.x):
35.0.0 / 35.0.1 both tried
- Operating system and version CLIENT
- Windows 11
- Is this the first time you’ve seen this error? (Yes / No):
NO
- When did this problem seem to first start?
2026-10-31. I think it was related to 35.0.0 → 35.0.1 update, but I’m not sure.
- Installation method CLIENT
msi
- Are you using CloudfIare, mod_security, or similar? (Yes / No)
I don't think so
Summary of the issue you are facing:
Problem is now solved.
Problem was:
Nextcloud Files doesn’t start.
Nothing happens when I try to start it manually by starting .
Steps to replicate it (hint: details matter!):
-
Launch application
-
Reboot attempted
Solution:
Uninstall Nextcloud
Rename the sync folder (Nextcloud folder)
Install Nextcloud
The client now starts
Remove folder sync connection (was remembered from previous config)
Add a new folder sync connection
The old, renamed folder can maybe be deleted using this method: I’m trying to mark it as not a cloud provider with this command: “attrib -P -U -O “C:\Users\mariu\Nextcloudaaaaa” /s /d”
Log entries
Nextcloud Files Client log
2026-11-01 14:00:46:482 [ info nextcloud.gui.application C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\application.cpp:975 ]: ################## "Nextcloud" locale: "en_GB" ui_lang: QVariant(Invalid) version: "35.0.1 (build 20261029)" os: "Windows 11 Version 25H2" platform: "windows"
2026-11-01 14:00:46:482 [ info nextcloud.gui.application C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\application.cpp:981 ]: Arguments: QList("C:\\Program Files\\Nextcloud\\nextcloud.exe")
2026-11-01 14:00:46:482 [ info nextcloud.gui.application C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\application.cpp:1284 ]: System UI languages are: QList("en-Latn-GB", "en-GB", "en-Latn", "en")
2026-11-01 14:00:46:483 [ info nextcloud.gui.application C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\application.cpp:1301 ]: selected application language: "en_Latn_GB"
2026-11-01 14:00:46:484 [ info nextcloud.gui.application C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\application.cpp:1308 ]: Using "en_Latn_GB" translation
2026-11-01 14:00:46:486 [ info nextcloud.gui.application C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\application.cpp:156 ]: This is not an upgrade/downgrade/migration. Proceed to read current application config file.
2026-11-01 14:00:46:486 [ warning nextcloud.gui.application C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\application.cpp:356 ]: Config version migration was not possible.
2026-11-01 14:00:46:516 [ info nextcloud.gui.application C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\application.cpp:409 ]: VFS windows plugin is available
2026-11-01 14:00:46:542 [ info nextcloud.gui.application C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\application.cpp:413 ]: VFS suffix plugin is available
2026-11-01 14:00:46:544 [ info nextcloud.gui.socketapi C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\socketapi\socketapi.cpp:305 ]: Listen started.
2026-11-01 14:00:46:544 [ info nextcloud.gui.folder.manager C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\folderman.cpp:71 ]: setting remote poll timer interval to 30000 msec
2026-11-01 14:00:46:545 [ info nextcloud.gui.account.manager C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\accountmanager.cpp:171 ]: Checking for accounts versions.
2026-11-01 14:00:46:545 [ info nextcloud.gui.account.manager C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\accountmanager.cpp:172 ]: Config accounts version: 13
2026-11-01 14:00:46:545 [ info nextcloud.gui.account.manager C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\accountmanager.cpp:173 ]: Max accounts Version is set to: 13
2026-11-01 14:00:46:689 [ info nextcloud.gui.account.manager C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\accountmanager.cpp:648 ]: Account for QUrl("https://server.example.com:8080") using auth type "webflow"
2026-11-01 14:00:46:689 [ info nextcloud.sync.credentials.webflow C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\creds\webflowcredentials.cpp:116 ]: Get QNAM
2026-11-01 14:00:46:696 [ info nextcloud.gui.account.manager C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\accountmanager.cpp:723 ]: Restored: 0 unknown certs.
2026-11-01 14:00:46:774 [ info nextcloud.gui.folder.manager C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\folderman.cpp:205 ]: Setup folders from settings file
2026-11-01 14:00:46:774 [ info nextcloud.gui.folder.manager C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\folderman.cpp:484 ]: FolderDefinition::maxSettingsVersion: 13
2026-11-01 14:00:46:774 [ info nextcloud.gui.folder.manager C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\folderman.cpp:484 ]: FolderDefinition::maxSettingsVersion: 13
2026-11-01 14:00:46:774 [ info nextcloud.gui.folder.manager C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\gui\folderman.cpp:484 ]: FolderDefinition::maxSettingsVersion: 13
2026-11-01 14:00:46:775 [ info plugins C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\vfs.cpp:293 ]: Created VFS instance from plugin "nextcloudsync_vfs_cfapi"
2026-11-01 14:00:46:775 [ info nextcloud.sync.database C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\syncjournaldb.cpp:92 ]: Detected filesystem "NTFS" for "C:/Users/mariu/Nextcloud/.sync_97ef48d17f0f.db"
2026-11-01 14:00:46:778 [ info nextcloud.sync.configfile C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\libsync\configfile.cpp:1523 ]: Adding user defined ignore list to csync: "C:/Users/mariu/AppData/Roaming/Nextcloud/sync-exclude.lst"
2026-11-01 14:00:46:780 [ info nextcloud.sync.vfs.cfapi.wrapper C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\libsync\vfs\cfapi\cfapiwrapper.cpp:854 ]: Successfully set Registry keys for shell integration at: "SOFTWARE\\Microsoft\\Windows\\CurrentVersion\\Explorer\\SyncRootManager\\Nextcloud!S-1-5-21-2356509602-1878028731-3561799822-1002!fa2k@server.example.com:8080!1" . Progress bar will work.
2026-11-01 14:00:47:062 [ info nextcloud.sync.database C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\syncjournaldb.cpp:342 ]: sqlite3 version "3.50.4"
2026-11-01 14:00:47:062 [ info nextcloud.sync.database C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\syncjournaldb.cpp:355 ]: sqlite3 locking_mode= "exclusive"
2026-11-01 14:00:47:062 [ info nextcloud.sync.database C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\syncjournaldb.cpp:363 ]: sqlite3 journal_mode= "wal"
2026-11-01 14:00:47:062 [ info nextcloud.sync.database C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\syncjournaldb.cpp:386 ]: sqlite3 synchronous= "NORMAL"
2026-11-01 14:00:47:072 [ info nextcloud.sync.vfs.cfapi.wrapper C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\libsync\vfs\cfapi\cfapiwrapper.cpp:627 ]: ls prop requested "C:\\Users\\mariu\\Nextcloud" ""
2026-11-01 14:00:47:170 [ warning nextcloud.sync.database.sql C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\ownsql.cpp:308 ]: Sqlite exec statement error: 19 "UNIQUE constraint failed: metadata.inode" in "CREATE UNIQUE INDEX IF NOT EXISTS metadata_unique_inode ON metadata(inode);"
2026-11-01 14:00:47:171 [ warning nextcloud.sync.database C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\syncjournaldb.cpp:293 ]: SQL Error "updateMetadataTableStructure: create index unique inode" "UNIQUE constraint failed: metadata.inode"
2026-11-01 14:00:47:175 [ critical default C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\syncjournaldb.cpp:295 ]: ASSERT: "false" in file C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\syncjournaldb.cpp, line 295
2026-11-01 14:00:47:175 [ warning nextcloud.sync.database C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\syncjournaldb.cpp:268 ]: ERROR starting transaction: ""
2026-11-01 14:00:47:175 [ warning nextcloud.sync.database.sql C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\ownsql.cpp:254 ]: Sqlite prepare statement error: "out of memory" in "CREATE INDEX IF NOT EXISTS metadata_path ON metadata(path);"
2026-11-01 14:00:47:175 [ fatal default C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\ownsql.cpp:255 ]: ENFORCE: "allow_failure" in file C:\Users\User\AppData\Local\Temp\windows-42793\client-building\desktop\src\common\ownsql.cpp, line 255 with message: SQLITE Prepare error
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