Drupal 8.x

Hello

after changing menu settings suddenly got this error message:
Recoverable fatal error: Argument 1 passed to Drupal\views\ViewExecutableFactory::get() must implement interface Drupal\views\ViewEntityInterface, null given, called in /home/tohtereu/public_html/core/modules/views/src/Plugin/Menu/ViewsMenuLink.php on line 99 and defined in Drupal\views\ViewExecutableFactory->get() (line 70 of core/modules/views/src/ViewExecutableFactory.php).
The menu named "Main menu" is not working and when i go to change this menu then I get this error message.

When the site was moved from the development environment to the production environment most admin links have disappeared.

I have installed Drupal 8 and enabled the Web Services modules, including REST UI. I read tons of discussions on how to use the REST api. I, however, do not manage to create or update nodes. Is there anyone who would like to review my installation and the way I use the interface? Please contact me.

Once I know what the problem is, what I do wrong, I will post it in this topic in detail. Hopefully others can take advantage of that.

On D8 i created a view with an exposed filter.
I placed the filters in a block, so it can be displayed in a sidebar.

But i wonder how i can display all terms with a checkfield instead of a drop-down list.
You know...Like ebay..., when refining a search.

Hi all, new to the world of Drupal but a long-time IT guy. I've got Drupal 8.1.1 installed on a shared host through 1&1, and it seems like a successful install, but the default theme is missing and I can't load any of the configuration pages (guessing because the CSS is missing so the links fail). I'm still researching the forums for similar problems, so if there's an existing post please point me in the that direction.

Hi,

is it possible with D8.1 and the recent rules module to create a rule to send an email to the author of a node after someone hast left a comment there? Or does rules still doesnt support tokens in the D8 release?

hope for help, thanks!