Contacts not working with NC12

[Dennis1993]

Steps to reproduce

1. Install fresh NextCloud 12 instance
2. activate the contacts app
3. now you see a Spinning Wheel
4. add a contact shows errors

Expected behaviour

Spinning wheel and app completly not working

Actual behaviour

No spinning wheel and usable app

Server configuration

Operating system:
Ubuntu 17.04

Web server:
Apache 2.4

Database:
MySQL 5.7

PHP version:
PHP 7.1

Nextcloud version: (see Nextcloud admin page)
12.0.0

Contacts version: (see Nextcloud apps page)
1.5.3

Updated from an older Nextcloud or fresh install:
fresh installation

List of activated apps:
Default apps with Calendar (1.5.3) and contacts (1.5.3)

Client configuration

Browser:
Firefox 53.0.3

Operating system:
Windows 10

Opening the app shows that:

If I click on "Neuer Kontakt" this error appear:

[kiwiufa]

I'm experiencing very similar issue with nextcloud 12.0. It seems to work for a user admin, but not for any other user (not even for users with admin privileges).
After a click on "+ New contact" I receive the following error:
TypeError: Cannot read property 'displayName' of undefined
at new Contact (contact_model.js:12)
at Object.create (contact_service.js:86)
at Object.ctrl.createContact (newContactButton_controller.js:10)
at fn (eval at compile (angular.js?v=0ccff16…-0:14817), :4:269)
at expensiveCheckFn (angular.js?v=0ccff16…-0:15906)
at callback (angular.js?v=0ccff16…-0:25885)
at Scope.$eval (angular.js?v=0ccff16…-0:17682)
at Scope.$apply (angular.js?v=0ccff16…-0:17782)
at HTMLButtonElement. (angular.js?v=0ccff16…-0:25890)
at HTMLButtonElement.dispatch (core.js?v=0ccff16…-0:3)

I have a similar setup:
Raspbian 8 Jessie
Nextcloud 12.0.0
Apache 2.4.25
PHP 7.0
MariaDB 10

Contacts app version 1.5.3

[lolihunter]

This is simple to fix.

There is no default address book created in nextcloud 12. simple use the settings below and enter a new name for a address book, example "Personal", then hit enter.

After creating one you can import contacts or create them.

[kiwiufa]

Thank you. The above has fixed the issue for me

[irgendwie]

In the upcoming version of contacts, an address-book is automatically created in case none is existing. Normally Nextcloud/server also automatically creates one, once a new user is created.

[hognoodle]

Thanks lolihunter, that was all I needed.