Failure sharing file

Hi there,

I am using Nextcloud 11 fresh installed on Ubuntu 14,04. All things work fine until a normal user wants to share a file via mail address.
The user is typing in the mail address and after pressing enter the following message appears in top of the window: "The given object name is invalid’ .
After a reload of the page the mail address appears under the shared tab and the mail is also send out to the recepient.
I just looked into the network trace and there is the following error showing up:
https://media.academymaker.de/ocs/v2.php/apps/files_sharing/api/v1/shares?format=json HTTPS POST 403 application/json 109 B 313,71 ms XMLHttpRequest

So I get a 403 error on the URL https://SERVERNAME/ocs/v2.php/apps/files_sharing/api/v1/shares?format=json.
When an admin user is sharing a file via mail address everything works fine and there is no error showing up.
I would appreciate if someone can help me on this topic!

Best regards
Johannes

Is there nobody who can help on this topic? :slight_smile: