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Sorry to hear you’re facing problems 
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Or for longer, use three backticks above and below the code snippet:
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NextcloudPi version v1.53.0
Nextcloud version (eg, 20.0.5): 27.1.3.2
Operating system and version (eg, Ubuntu 20.04): Debian GNU/Linux 11. 5.15.61-v8+
The issue you are facing:
I cant upload files bigger than ~20kb to Nextcloud. Almost empty textfiles work. But at around 3k words the file gets to big.
Error Message:
Erwartete Dateigröße von 10485760 bytes, aber 8192 bytes gelesen (vom Nextcloud-Client) und geschrieben (in den Nextcloud-Speicher). Dies kann entweder ein Netzwerkproblem auf der sendenden Seite oder ein Problem beim Schreiben in den Speicher auf der Serverseite sein.
Steps to replicate it:
- Upload a File to Nextcloud
The output of your Nextcloud log in Admin > Logging:
Fehler no app in context Sabre\DAV\Exception\BadRequest: Erwartete Dateigröße von 10485760 bytes, aber 8192 bytes gelesen (vom Nextcloud-Client) und geschrieben (in den Nextcloud-Speicher). Dies kann entweder ein Netzwerkproblem auf der sendenden Seite oder ein Problem beim Schreiben in den Speicher auf der Serverseite sein.
/var/www/nextcloud/apps/dav/lib/Connector/Sabre/Directory.php - line 149:
OCA\DAV\Connector\Sabre\File->put()
/var/www/nextcloud/apps/dav/lib/Upload/UploadFolder.php - line 50:
OCA\DAV\Connector\Sabre\Directory->createFile("*** sensiti ... *")
/var/www/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 1098:
OCA\DAV\Upload\UploadFolder->createFile("*** sensiti ... *")
/var/www/nextcloud/3rdparty/sabre/dav/lib/DAV/CorePlugin.php - line 504:
Sabre\DAV\Server->createFile("*** sensiti ... *")
/var/www/nextcloud/3rdparty/sabre/event/lib/WildcardEmitterTrait.php - line 89:
Sabre\DAV\CorePlugin->httpPut()
/var/www/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 472:
Sabre\DAV\Server->emit()
/var/www/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 253:
Sabre\DAV\Server->invokeMethod()
/var/www/nextcloud/3rdparty/sabre/dav/lib/DAV/Server.php - line 321:
Sabre\DAV\Server->start()
/var/www/nextcloud/apps/dav/lib/Server.php - line 365:
Sabre\DAV\Server->exec()
/var/www/nextcloud/apps/dav/appinfo/v2/remote.php - line 35:
OCA\DAV\Server->exec()
/var/www/nextcloud/remote.php - line 172:
require_once("/var/www/ne ... p")
2023-12-25T22:01:53+0100
Fehler PHP fread(): Unable to create temporary file, Check permissions in temporary files directory. at /var/www/nextcloud/3rdparty/icewind/streams/src/Wrapper.php#55
2023-12-25T22:01:53+0100
Fehler PHP fread(): file created in the system's temporary directory at /var/www/nextcloud/3rdparty/icewind/streams/src/Wrapper.php#55
The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):
In other threads it seemed to be a problem with php but i dont understood the solution. Im very new to this and still trying to figure things out.
If i can give you more information just let me know (and maybe how do it).
have a nice week