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example
Or for longer, use three backticks above and below the code snippet:
longer
example
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Some or all of the below information will be requested if it isn’t supplied; for fastest response please provide as much as you can 
Nextcloud version (eg, 12.0.2): 13.0.5
Operating system and version (eg, Ubuntu 17.04): Ubuntu 16.04 LTS
Apache or nginx version (eg, Apache 2.4.25): Apache 2.4.29
PHP version (eg, 7.1): 7.0.27
The issue you are facing:
Is this the first time you’ve seen this error? (Y/N): Y
Steps to replicate it:
- Syncing contacts using DAVdroid does not work. No contacts show up under Contacts in NC. Setup DAVdroid using Nextcloud app and attempted manual setup with the same results. Tried both Groups are separate VCards and Groups are per-contact categories in DAVdroid.
The output of your Nextcloud log in Admin > Logging:
Debug webdav Sabre\DAV\Exception\NotFound: File not found: groups in 'addressbooks'
/var/www/html/nextcloud/3rdparty/sabre/dav/lib/DAV/Tree.php - line 76: Sabre\DAV\SimpleCollection->getChild('groups')
/var/www/html/nextcloud/3rdparty/sabre/dav/lib/DAV/Tree.php - line 71: Sabre\DAV\Tree->getNodeForPath('addressbooks/gr...')
/var/www/html/nextcloud/apps/end_to_end_encryption/lib/Connector/Sabre/LockPlugin.php - line 144: Sabre\DAV\Tree->getNodeForPath('addressbooks/gr...')
/var/www/html/nextcloud/apps/end_to_end_encryption/lib/Connector/Sabre/LockPlugin.php - line 114: OCA\EndToEndEncryption\Connector\Sabre\LockPlugin->getNode('addressbooks/gr...', 'PROPFIND')
[internal function] OCA\EndToEndEncryption\Connector\Sabre\LockPlugin->checkLock(Object(Sabre\HTTP\Request), Object(Sabre\HTTP\Response))
/var/www/html/nextcloud/3rdparty/sabre/event/lib/EventEmitterTrait.php - line 105: call_user_func_array(Array, Array)
/var/www/html/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 466: Sabre\Event\EventEmitter->emit('beforeMethod', Array)
/var/www/html/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 254: Sabre\DAV\Server->invokeMethod(Object(Sabre\HTTP\Request), Object(Sabre\HTTP\Response))
/var/www/html/nextcloud/apps/dav/lib/Server.php - line 287: Sabre\DAV\Server->exec()
/var/www/html/nextcloud/apps/dav/appinfo/v2/remote.php - line 35: OCA\DAV\Server->exec()
/var/www/html/nextcloud/remote.php - line 164: require_once('/var/www/html/n...')
{main}
The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):
<?php
$CONFIG = array (
'instanceid' => 'INSTANCEID',
'passwordsalt' => 'THEPASSWORDSALT',
'trusted_domains' =>
array (
0 => '192.168.XXX.XXX',
1 => 'cloud.domain.tld',
),
'trusted_proxies' =>
array (
0 => '192.168.xxx.xxx',
),
'forwarded_for_headers' =>
array (
0 => 'HTTP_X_FORWARDED_FOR',
),
'auth.bruteforce.protection.enabled' => true,
'datadirectory' => '/mnt/raid/owncloud/data',
'dbtype' => 'mysql',
'version' => '13.0.5.2',
'dbname' => 'owncloud',
'dbhost' => 'localhost',
'dbtableprefix' => 'oc_',
'dbuser' => 'ncuser',
'dbpassword' => 'ncpass',
'installed' => true,
'forcessl' => true,
'mail_smtpmode' => 'smtp',
'mail_from_address' => 'postmaster',
'mail_domain' => 'domain.tld',
'mail_smtphost' => 'smtp.domain.tld',
'mail_smtpport' => '25',
'loglevel' => 0,
'theme' => '',
'maintenance' => false,
'secret' => 'THESECRET',
'trashbin_retention_obligation' => 'auto',
'updatechecker' => false,
'memcache.distributed' => '\\OC\\Memcache\\Redis',
'memcache.local' => '\\OC\\Memcache\\Redis',
'memcache.locking' => '\\OC\\Memcache\\Redis',
'redis' =>
array (
'host' => 'localhost',
'port' => 6379,
'timeout' => 0.0,
),
'overwrite.cli.url' => 'https://cloud.domain.tld',
The output of your Apache/nginx/system log in /var/log/____:
192.168.xxx.xxx - user [10/Aug/2018:08:38:31 -0400] "PROPFIND /remote.php/dav /addressbooks/users/user/Contacts/ HTTP/1.0" 207 3197 "-" "DAVdroid/2.0-gpla y (2018/07/30; dav4android; okhttp/3.11.0) Android/8.0.0"