New install on nethserver, internal server error trying to log in to nextcloud

Nextcloud version (eg, 10.0.2):cannot log in to find it
Operating system and version (eg, Ubuntu 16.04):Nethserver 7.3.1611
Apache or nginx version (eg, Apache 2.4.25): none
PHP version (eg, 5.6):5.4.16
Is this the first time you’ve seen this error?:never managed to log in yet

Please note also I am using windows AD from a 2012 server, for accounts.
I have noted the comment in the ‘known bugs’ section and I have created a user to bind for read-only access.

Can you reliably replicate it? (If so, please outline steps):yes, whether using LAN address or from outside, same result

The issue you are facing:I just get a request reference (Request ID: Wc0UdT8BgpN56BUfscvAvAAAAAE)

The output of your Nextcloud log in Admin > Logging: (can I get this without logging in?)

The output of your config.php file in /path/to/nextcloud (make sure you remove any identifiable information!):

$CONFIG = array (
  'passwordsalt' => 'RN73TF9iHu6uqHpbdFhS1btBbjVLgi',
  'secret' => 'SQFfN/J5UTE8CGnCkaWiZAevV8+4ZnPi2aa6ZNvzPbeFIa8x',
  'trusted_domains' => 
  array (
    0 => 'localhost',
    1 => 'rnt01',
    2 => '',
    3 => '',
    4 => '',
  'datadirectory' => '/var/lib/nethserver/nextcloud/',
  'overwrite.cli.url' => 'http://localhost',
  'dbtype' => 'mysql',
  'version' => '',
  'dbname' => 'nextcloud',
  'dbhost' => 'localhost',
  'dbport' => '',
  'dbtableprefix' => 'oc_',
  'dbuser' => 'nextcloud',
  'dbpassword' => 'r4vhKsm2fY3PLsE2',
  'installed' => true,
  'instanceid' => 'och0dlk2amk7',
  'ldapIgnoreNamingRules' => false,
  'ldapProviderFactory' => '\\OCA\\User_LDAP\\LDAPProviderFactory',
  'maintenance' => false,
  'mail_smtpmode' => 'smtp',
  'mail_smtpauthtype' => 'LOGIN',
  'mail_from_address' => 'rich',
  'mail_domain' => '',
  'mail_smtphost' => '',
  'mail_smtpauth' => 1,
  'mail_smtpname' => '',
  'mail_smtppassword' => 'xxx',

The output of your Apache/nginx/system log in /var/log/____:

You have Nextcloud 12.0.2. Before you set up windows AD, can you login on your Nextcloud? I would keep at least one admin user as native Nextcloud user which is not managed through AD. It is hard to tell like this if your problem is related to AD.

Can you check your server logfile (/var/log/apache/error.log not sure for nethservers) for more details on the internal server error.