Can't delete files

Hi everyone,
I'm in trouble with ownCloud 8.2 and Desktop client 2.2.4 build 6408.
I uploaded several files larger than 3 GB. In details, they are 3.5, 3.6, 3.7, 3.5 and 3.8 GB sized and they are located within a single subfolder.
When I try to eliminate them, I can only delete the local copy of the files, as they are still on the server.
As I use the web browser to eliminate the files, it says "Could not delete: name_of_file".
It is also impossible to rename them.
I can share them with other users but they can't delete files either.
I'm sure that I can eliminate file tgrough web interface and desktop client within 800 MB size.

With reference to what said and the aforementioned operations performed, the output log file is reported here.

Thank you all in advance for any suggestion.

{"reqId":"w2xXplTbC6Y9DurvgvRB","remoteAddr":"172.17.200.2","app":"webdav","message":"Exception:

{\"Message\":\"HTTP\\/1.1 423 \\"DATEX
II\\/Dati\\/DatexII_captures\\" is
locked\",\"Exception\":\"OC\\Connector\\Sabre\\Exception\\FileLocked\",\"Code\":0,\"Trace\":\"#0

\\/var\\/www\\/html\\/cloud\\/3rdparty\\/sabre\\/dav\\/lib\\/DAV\\/CorePlugin.php(635):

OC\\Connector\\Sabre\\ObjectTree->move('DATEX
II\\/Dati\\/D...',
'DATEX II\\/DatexI...')\n#1 [internal function]:
Sabre\\DAV\\CorePlugin->httpMove(Object(Sabre\\HTTP\\Request),

Object(Sabre\\HTTP\\Response))\n#2
\\/var\\/www\\/html\\/cloud\\/3rdparty\\/sabre\\/event\\/lib\\/EventEmitterTrait.php(105):

call_user_func_array(Array, Array)\n#3
\\/var\\/www\\/html\\/cloud\\/3rdparty\\/sabre\\/dav\\/lib\\/DAV\\/Server.php(469):

Sabre\\Event\\EventEmitter->emit('method:MOVE', Array)\n#4
\\/var\\/www\\/html\\/cloud\\/3rdparty\\/sabre\\/dav\\/lib\\/DAV\\/Server.php(254):

Sabre\\DAV\\Server->invokeMethod(Object(Sabre\\HTTP\\Request),

Object(Sabre\\HTTP\\Response))\n#5
\\/var\\/www\\/html\\/cloud\\/apps\\/files\\/appinfo\\/remote.php(56):

Sabre\\DAV\\Server->exec()\n#6
\\/var\\/www\\/html\\/cloud\\/remote.php(137):
require_once('\\/var\\/www\\/html\\/c...')\n#7
{main}\",\"File\":\"\\/var\\/www\\/html\\/cloud\\/lib\\/private\\/connector\\/sabre\\/objecttree.php\",\"Line\":239}","level":4,"time":"2016-11-08T15:06:07+00:00","method":"MOVE","url":"\/cloud\/remote.php\/webdav\/DATEX%20II\/Dati\/DatexII_captures"}

{"reqId":"Ham7otTPkFkrOOYKysAb","remoteAddr":"172.17.200.2","app":"webdav","message":"Exception:

{\"Message\":\"HTTP\\/1.1 423 \\"Virtual Machines\\" is
locked\",\"Exception\":\"OC\\Connector\\Sabre\\Exception\\FileLocked\",\"Code\":0,\"Trace\":\"#0

\\/var\\/www\\/html\\/cloud\\/3rdparty\\/sabre\\/dav\\/lib\\/DAV\\/Tree.php(179):

OC\\Connector\\Sabre\\Directory->delete()\n#1
\\/var\\/www\\/html\\/cloud\\/3rdparty\\/sabre\\/dav\\/lib\\/DAV\\/CorePlugin.php(287):

Sabre\\DAV\\Tree->delete('Virtual Machine...')\n#2 [internal
function]:
Sabre\\DAV\\CorePlugin->httpDelete(Object(Sabre\\HTTP\\Request),

Object(Sabre\\HTTP\\Response))\n#3
\\/var\\/www\\/html\\/cloud\\/3rdparty\\/sabre\\/event\\/lib\\/EventEmitterTrait.php(105):

call_user_func_array(Array, Array)\n#4
\\/var\\/www\\/html\\/cloud\\/3rdparty\\/sabre\\/dav\\/lib\\/DAV\\/Server.php(469):

Sabre\\Event\\EventEmitter->emit('method:DELETE', Array)\n#5
\\/var\\/www\\/html\\/cloud\\/3rdparty\\/sabre\\/dav\\/lib\\/DAV\\/Server.php(254):

Sabre\\DAV\\Server->invokeMethod(Object(Sabre\\HTTP\\Request),

Object(Sabre\\HTTP\\Response))\n#6
\\/var\\/www\\/html\\/cloud\\/apps\\/files\\/appinfo\\/remote.php(56):

Sabre\\DAV\\Server->exec()\n#7
\\/var\\/www\\/html\\/cloud\\/remote.php(137):
require_once('\\/var\\/www\\/html\\/c...')\n#8
{main}\",\"File\":\"\\/var\\/www\\/html\\/cloud\\/lib\\/private\\/connector\\/sabre\\/directory.php\",\"Line\":251}","level":4,"time":"2016-11-08T15:06:07+00:00","method":"DELETE","url":"\/cloud\/remote.php\/webdav\/Virtual%20Machines"}

Hi,

a FAQ containing all known infos about this "file is locked" issue is available here: