Calddav or carddav resolving

I have a Nextcloud Version 13.0.12 server in the /nexcloud directory on a Slackware 14.2 server running PHP 5.6.40. PHP7 is not available on this Slackware 14.2, so I cannot to upgrade without significant risks. I am using the Apache Web Server. The client is another Linux box, and my web browsers are Firefox or Seamonkey.

I am reading the following messages on settings:

  1. Your web server is not properly set up to resolve “/.well-known/caldav”. Further information can be found in the documentation.
  2. Your web server is not properly set up to resolve “/.well-known/carddav”. Further information can be found in the documentation.
  3. You are currently running PHP 5.6.40. Upgrade your PHP version to take advantage of performance and security updates provided by the PHP Group as soon as your distribution supports it.

On logging in “nextcloud/.well-known/caldav” or “nextcloud/.well-known/carddav” from my desktop web browser, I get an authentication pop-up. On entering my credentials I get redirected to “/remote.php/dav/”and this this message on the web browser:

This is the WebDAV interface. It can only be accessed by WebDAV clients such as the Nextcloud desktop sync client.

I read the linked documentation, it appears that the two URL posted above were redirected correctly. However, when I try to access “/nextcloud/.well-known/webfinger”. I do not get redirected and I get this error message:

Internal Server Error

The server was unable to complete your request.

If this happens again, please send the technical details below to the server administrator.

More details can be found in the server log.

Technical details

  • Remote Address: my_ip
  • Request ID: bU86bvupMvVtFdYGreh9

If I try to log in “/nextcloud/public.php?service=webfinger”, I get a similar error message.

On my server:

root@brix:/var/www/htdocs/nextcloud# grep RewriteRule .htaccess

RewriteRule ^$ /remote.php/webdav/ [L,R=302]

RewriteRule .* - [env=HTTP_AUTHORIZATION:%{HTTP:Authorization}]

RewriteRule ^.well-known/host-meta /nextcloud/public.php?service=host-meta [QSA,L]

RewriteRule ^.well-known/host-meta.json /nextcloud/public.php?service=host-meta-json [QSA,L]

RewriteRule ^.well-known/webfinger /nextcloud/public.php?service=webfinger [QSA,L]

RewriteRule ^.well-known/carddav /nextcloud/remote.php/dav/ [R=301,L]

RewriteRule ^.well-known/caldav /nextcloud/remote.php/dav/ [R=301,L]

RewriteRule ^remote/(.*) remote.php [QSA,L]

RewriteRule ^(?:build|tests|config|lib|3rdparty|templates)/.* - [R=404,L]

RewriteRule ^(?:.|autotest|occ|issue|indie|db_|console).* - [R=404,L]

On my logs, I read:

{“reqId”:“MEo0ZpZcVRwVPuPqGpyR”,“level”:3,“time”:“2019-05-13T11:47:38+00:00”,“remoteAddr”:"< my_ip >",“user”:"–",“app”:“public”,“method”:“GET”,“url”:"/nextcloud/.well-known/webfinger",“message”:“Exception: {“Exception”:“Exception”,“Message”:“App not installed: “,“Code”:0,“Trace”:”#0 {main}”,“File”:”\/var\/www\/htdocs\/nextcloud\/public.php",“Line”:72}",“userAgent”:“Mozilla/5.0 (X11; Linux x86_64; rv:52.0) Gecko/20100101 Firefox/52.0 SeaMonkey/2.49.4”,“version”:“13.0.12.1”}

What App am I missing? From Internet searches, I think that it is the Social App, but I do not find it for NC13.

Besides that my PHP is outdated, will you please let me know if there is something else I can do to resolve this error message?