Situation

In the WebModel, it is possible to save certain objects as favorites or to follow them. When you follow an object, a star symbol {{1}} appears in the top right corner of the object properties.
You can find out how to follow objects in the WebModel on the ››› Properties window in the WebModel.

You can usually unfollow the object by clicking the star icon. If a loading icon (progress circle) appears that only disappears when you close the properties window and displays 405 Method Not Allowed {{2}} for the HTTP verb DELETE in the browser's development tool (usually the F12 key), proceed as described below. 

Solution

The WEB DAV module is probably activated on the IIS (Internet Information Services).

1. Open IIS Manager.
2. Click on the WebModel website.
3. Click Modules.
4. Select the WebDAVModule {{3}} and click Remove {{4}}.
   
5. Close IIS Manager.