Problem – Edit Entry and Front-End View

I hope everbody finds this thread before searching in the source for a long time.

Because I did ??

System: WordPress 4.7.3 , Apache, Standardtheme and no other Plugins (I deleted every other Plugin with files and transienst in the database)

Problem: After some submissions in the form i wanted to look into the details in the backend. To edit the entries was broken and the shortcode in frontend , too.
For ex.: Shortcode [caldera_forms_entry_viewer id=”XXXXXX”]

So after a while the error was found. The Permalink structure. My live-system is in a very restrictive setting without write permission -> also without .htaccess

The error was shown in the browser-console;
404 ; GET ; TYP:json
domain.de/?rest_route=/cf-api/v2/entries/CF58d2938be5ce6?page=1&per_page=20

After installing the live system in the dev setting and after changing the permalink into: /%postname%/ -> everything was fine.

I hope this thread finds somebody helpful.

greetings