Federation: not possible when fully encrypted nextcloud

Hi,

a friend of mine sent me a file with the federation feature. His nextcloud files are not encrypted - my files are encrypted (default encryption module). After accepting the federation invitation, I hadn´t any file at “Files shared with you”. I found the following errors:

app":“core”,“message”:“Default encryption module not loaded”,“level”:3,“time”:“2017-04-04T15:42:21+02:00”,“method”:“GET”,“url”:"/ocs/v1.php/apps/files_sharing/api/v1/shares?format=json&shared_with_me=true",“version”:“11.0.2.7”}

Nextcloud version (eg, 10.0.2): 11.0.2.7
Operating system and version (eg, Ubuntu 16.04): Debian 8
Apache or nginx version (eg, Apache 2.4.25): nginx 1.10.3
PHP version (eg, 5.6): 7.0
Is this the first time you’ve seen this error?: yes

Can you reliably replicate it? (If so, please outline steps):
Encrypt your nextcloud with the default encryption module, accept a federation sharing from another nextcloud user, who hasn´t encrypted his nextcloud.

The issue you are facing:
Can´t get any file by federation sharing.

The output of your Nextcloud log in Admin > Logging:
app":“core”,“message”:“Default encryption module not loaded”,“level”:3,“time”:“2017-04-04T15:42:21+02:00”,“method”:“GET”,“url”:"/ocs/v1.php/apps/files_sharing/api/v1/shares?format=json&shared_with_me=true",“version”:“11.0.2.7”}
Error PHP Error: Call to a member function getMimetype() on boolean at /var/kunden/cloud/httpdocs/nextcloud/apps/files_sharing/lib/Controller/RemoteController.php#115

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):
$CONFIG = array (
‘instanceid’ => ‘’,
‘passwordsalt’ => ‘’,
‘secret’ => ‘’,
‘trusted_domains’ =>
array (
0 => ‘cloud.xx.de’,
),
‘datadirectory’ => ‘/var/cloud/files’,
‘overwrite.cli.url’ => ‘’,
‘dbtype’ => ‘mysql’,
‘version’ => ‘11.0.2.7’,
‘dbname’ => ‘nextcloud’,
‘dbhost’ => ‘localhost’,
‘dbport’ => ‘’,
‘dbtableprefix’ => ‘oc_’,
‘dbuser’ => ‘cloudxx’,
‘dbpassword’ => ‘’,
‘logtimezone’ => ‘Europe/Berlin’,
‘maintenance’ => false,
‘installed’ => true,
‘mail_from_address’ => ‘mail’,
‘mail_smtpmode’ => ‘php’,
‘mail_domain’ => ‘xx’,
‘memcache.local’ => ‘\OC\Memcache\APCu’,
‘theme’ => ‘’,
‘loglevel’ => 0,
‘enabledPreviewProviders’ =>
array (
0 => ‘OC\Preview\Image’,
1 => ‘OC\Preview\MP3’,
2 => ‘OC\Preview\TXT’,
3 => ‘OC\Preview\MarkDown’,
4 => ‘OC\Preview\PDF’,
5 => ‘OC\Preview\OpenDocument’,
6 => ‘OC\Preview\StarOffice’,
7 => ‘OC\Preview\MSOfficeDoc’,
8 => ‘OC\Preview\MSOffice2003’,
9 => ‘OC\Preview\MSOffice2007’,
10 => ‘OC\Preview\Epub’,
11 => ‘OC\Preview\FB2’,
),
);

The output of your Apache/nginx/system log in /var/log/____:
No output