Working with (xls, xlsx) in owncloud

On the server, set libreOffise. Format doc and docx opened and edited. The web interface does not open Excel (xls, xlsx)
Config.php - 'preview_libreoffice_path' => '/ usr / bin / libreoffice',
How to teach owncloud open (xls, xlsx) for collaborative editing?

Server configuration
Operating system: Ubuntu Server 15.10
Web server:Apache/2.4.12
Database:mariaDB 10.0.25
PHP version:PHP 5.6.11
ownCloud version (see ownCloud admin page): OwnCloud 8.2.9 (stable)

Hi,

having a look at the documentation is telling you that .xls and .xlsx are not supported for the app you're trying to use:

Supported file formats are .odt, .doc, and .docx. .odt is supported natively in ownCloud, and you must have LibreOffice or OpenOffice installed on the ownCloud server to convert .doc, and .docx documents.

-> https://doc.owncloud.org/server/latest/admin_manual/configuration_files/collaborative_documents_configuration.html

If you want to edit .xls and .xlsx you need to have a look into Collabora Online: