Webdav office lock files

After updated to 9.1.6 our users noticed a strange behaviour using webdav. The MS office lock files (~$....) are created as usually once open an office file, but at the same second they are deleted even if the file is open.
We loose the capability to know if another user is editing the file.

Server configuration

Operating system:
Windows 8.1 webdav

Web server:
CentOS Linux release 7.3.1611

Database:
Maria-DB 5.5.52

PHP version:
7.0.19

ownCloud version:
9.1.6.2

Updated from an older ownCloud or fresh install:
updated

Where did you install ownCloud from:
owncloud repositories

Signing status (ownCloud 9.0 and above):
No errors have been found.

The content of config/config.php:
{
"system": {
"theme": "REMOVED",
"instanceid": "oc4nolrr14dg",
"passwordsalt": "REMOVED SENSITIVE VALUE",
"secret": "REMOVED SENSITIVE VALUE",
"trusted_domains": [
"REMOVED",
"REMOVED",
"REMOVED",
"REMOVED"
],
"datadirectory": "\/home\/owncloud\/data",
"overwrite.cli.url": "http:\/\/***REMOVED***\/owncloud",
"dbtype": "mysql",
"version": "9.1.6.2",
"dbname": "owncloud",
"dbhost": "localhost",
"dbtableprefix": "oc_",
"dbuser": "REMOVED SENSITIVE VALUE",
"dbpassword": "REMOVED SENSITIVE VALUE",
"logtimezone": "Europe\/Lisbon",
"installed": true,
"ldapIgnoreNamingRules": false,
"loglevel": 3,
"mail_smtpmode": "smtp",
"mail_from_address": "REMOVED",
"mail_domain": "REMOVED",
"mail_smtphost": "REMOVED",
"mail_smtpport": "25",
"updatechecker": false,
"maintenance": false,
"singleuser": false,
"forcessl": true,
"enable_previews": true,
"preview_libreoffice_path": "\/usr\/bin\/libreoffice",
"enabledPreviewProviders": [
"OC\Preview\Image",
"OC\Preview\MP3",
"OC\Preview\TXT",
"OC\Preview\MarkDown"
],
"enable_avatars": true,
"allow_user_to_change_display_name": false,
"skeletondirectory": "",
"lost_password_link": "REMOVED",
"trashbin_retention_obligation": "30,auto",
"htaccess.RewriteBase": "\/owncloud",
"quota_include_external_storage": false,
"versions_retention_obligation": "auto",
"filelocking.enabled": true,
"memcache.locking": "\OC\Memcache\Redis",
"redis": {
"host": "localhost",
"port": 6379,
"timeout": 0,
"password": "REMOVED SENSITIVE VALUE"
},
"session_keepalive": true,
"session_lifetime": 172800,
"check_for_working_webdav": true
}
}

List of activated apps:

Enabled:
- activity: 2.3.2
- comments: 0.3.0
- configreport: 0.1.1
- dav: 0.2.7
- federatedfilesharing: 0.3.0
- files: 1.5.1
- files_pdfviewer: 0.8.1
- files_sharing: 0.10.0
- files_texteditor: 2.1
- files_trashbin: 0.9.0
- files_versions: 1.3.0
- firstrunwizard: 1.1
- notifications: 0.3.0
- provisioning_api: 0.5.0
- systemtags: 0.3.0
- templateeditor: 0.1
- updatenotification: 0.2.1
- user_ldap: 0.9.0

Are you using external storage, if yes which one: local/smb/sftp/...
no

Are you using encryption: yes/no
no

Are you using an external user-backend, if yes which one: LDAP/ActiveDirectory/Webdav/...
Active Directory

LDAP configuration (delete this part if not used)

+-------------------------------+--------------------------------------------------------------------------------------------------------------------------------------+
| Configuration | |
+-------------------------------+--------------------------------------------------------------------------------------------------------------------------------------+
| hasMemberOfFilterSupport | 1 |
| hasPagedResultSupport | |
| homeFolderNamingRule | attr:sAMAccountName |
| lastJpegPhotoLookup | 0 |
| ldapAgentName | REMOVED |
| ldapAgentPassword | *** |
| ldapAttributesForGroupSearch | |
| ldapAttributesForUserSearch | |
| ldapBackupHost | REMOVED |
| ldapBackupPort | |
| ldapBase | REMOVED |
| ldapBaseGroups | REMOVED |
| ldapBaseUsers | REMOVED |
| ldapCacheTTL | 600 |
| ldapConfigurationActive | 1 |
| ldapDynamicGroupMemberURL | |
| ldapEmailAttribute | mail |
| ldapExperiencedAdmin | 0 |
| ldapExpertUUIDGroupAttr | |
| ldapExpertUUIDUserAttr | |
| ldapExpertUsernameAttr | samaccountname |
| ldapGroupDisplayName | samaccountname |
| ldapGroupFilter | (&(|(objectclass=group))) |
| ldapGroupFilterGroups | |
| ldapGroupFilterMode | 1 |
| ldapGroupFilterObjectclass | |
| ldapGroupMemberAssocAttr | member |
| ldapHost | REMOVED |
| ldapIgnoreNamingRules | |
| ldapLoginFilter | (&(&(|(objectclass=person))(|(|(memberof=CN=Domain Users,CN=Users,REMOVED)(primaryGroupID=513))))(userPrincipalName=%uid)) |
| ldapLoginFilterAttributes | |
| ldapLoginFilterEmail | 0 |
| ldapLoginFilterMode | 1 |
| ldapLoginFilterUsername | 1 |
| ldapNestedGroups | 1 |
| ldapOverrideMainServer | |
| ldapPagingSize | 500 |
| ldapPort | 389 |
| ldapQuotaAttribute | extensionAttribute6 |
| ldapQuotaDefault | 5400000000 |
| ldapTLS | 0 |
| ldapUserDisplayName | displayName |
| ldapUserDisplayName2 | mail |
| ldapUserFilter | (&(|(objectclass=organizationalPerson))(|(|(memberof=CN=Domain Users,REMOVED)(primaryGroupID=513)))) |
| ldapUserFilterGroups | |
| ldapUserFilterMode | 1 |
| ldapUserFilterObjectclass | person |
| ldapUuidGroupAttribute | auto |
| ldapUuidUserAttribute | auto |
| turnOffCertCheck | 1 |
| useMemberOfToDetectMembership | 1 |
+-------------------------------+--------------------------------------------------------------------------------------------------------------------------------------+

With access to your command line run e.g.:
sudo -u www-data php occ ldap:show-config
from within your ownCloud installation folder

Without access to your command line download the data/owncloud.db to your local
computer or access your SQL server remotely and run the select query:
SELECT * FROM `oc_appconfig` WHERE `appid` = 'user_ldap';


Eventually replace sensitive data as the name/IP-address of your LDAP server or groups.

Client configuration

Browser:

Operating system:

Logs

Web server error log

Insert your webserver log here

ownCloud log (data/owncloud.log)

Insert your ownCloud log here

Browser log

Insert your browser log here, this could for example include:

a) The javascript console log
b) The network log 
c) ...

In which server version did it work the last time?

worked well in 'version' => '9.1.4.2'