Update ERROR 10.0.3

I can not install the update 10.0.3.

I have a notification in the AdminTool and click on it.
Then these two lines stand at the very top.

Warning: session_start (): Can not send session cookie - headers already sent (output started at /home/clients/96dc51f4fddcde3eb6702ed2f47e7a7a/owncloud/updater/app/bootstrap.php:22) in / home / clients / 96dc51f4fddcde3eb6702ed2f47e7a7a / owncloud / updater / app / bootstrap.php in line 46
Warning: session_start (): Can not send session cache limiter - headers were already sent (output started at /home/clients/96dc51f4fddcde3eb6702ed2f47e7a7a/owncloud/updater/app/bootstrap.php:22) in / home / clients / 96dc51f4fddcde3eb6702ed2f47e7a7a / owncloud / updater / app / bootstrap.php in line 46

If I click on Update, I get this info

Initialize = IO
Control system = undefined
undefined
Create a checkpoint
Downloading
Update kernel
Update apps
Stop the update
Done

He stays with Hacksystem and goes no further.
How do I install the update?

Hi,

if you have access to command line on your server you can install the update manually.

The documentation provides a good guide on how to do it.

https://doc.owncloud.com/server/10.0/admin_manual/maintenance/manual_upgrade.html

I do not have access to a CommandLine.
The my provider has a ToolStore and from there I could owncloud download and install.

Can I also uninstall my current Owncloud version (delete, without database and images in the directory) and reinstall and the existing uploaded data (pictures, etc) and reuse database in the new version

I don't know because I am not familiar with your hosted environment

I would load mycloud on my server, which I rented. no one else is on the server, just my pages.
but the offerer offers just apps on for rented server at.

Yeah, we recommend installing owncloud on servers that you have access to command line or can access vie ssh. Without that error detection and solving is near impossible.

I have owncloud re-installed (newest version) into a new database and then the existing database (user, file) into the existing database.
so hats worked.
the topic can be concluded