Hi Stephan,

Have you tried the solution given on below forum thread?

https://world.episerver.com/forum/developer-forum/-Episerver-75-CMS/Thread-Container/2017/4/the-store-was-queried-with-a-string-but-the-entity-id-is-a-undefined/

Thanks

Ravindra

Have you tried the solution given on below forum thread?

https://world.episerver.com/forum/developer-forum/-Episerver-75-CMS/Thread-Container/2017/4/the-store-was-queried-with-a-string-but-the-entity-id-is-a-undefined/

Yes, I have tried to configure <clientResources debug="true"> in the web.config but cannot find anything that targets the issue I am having..
Also no errors found in the logfiles and no 500 responses from the network in the browser.

Just found out when I search the page and select the the result, it gets selected and I am able to create the best bet.
But not through the treeview. It is visible and I can drill down into each node but I when I select it, I get the error.
I can only select the 'Root'.

This is the configuration for the indexing, don't know if it helps (I cannot even select pages of type `FaqItemPage`):

indexer.Conventions.DefaultIndexOptions = () =>
{
   return new IndexOptions { IndexAllLanguageVersions = true, FilterContent = true, IndexRelations = false };
};

indexer.Conventions.ForInstancesOf<PageData>().ShouldIndex(x => false);
indexer.Conventions.ForInstancesOf<BlockData>().ShouldIndex(x => false);
indexer.Conventions.ForInstancesOf<ImageData>().ShouldIndex(x => false);
indexer.Conventions.ForInstancesOf<ContentFolder>().ShouldIndex(x => false);

indexer.Conventions
       .ForInstancesOf<FaqItemPage>()
       .ShouldIndex(x => true)
       .IndexingInContentAreas(x => true)
       .IndexingChildrenOnMove(x => true);

I have tried disabling it all and reindex but makes no difference..

Is your site is multilingual? If yes then it might be possible that the root does not have a version of the specific language that you're editing.

Yes, the application is multisite and multilingual. I have tried preselecting the site and (master) language but it does not change the behaviour.

Please note; It is not a page I am editing but on EPiServer Find selecting an `best bet` page in the page tree.

While checking on this I found that this is a bug in EPiServer.CMS.UI 8.5.1.  I am not sure about earlier versions of Episerver but can you create a copy of your local instance and upgrade to some higher version(at least to EPiServer.CMS.UI 9.2.0) so that you can check whether it is a bug or some code issue on your local solution. Or you can reach out to Episever support about this.