Search Results webpart throws error before first search

Question

I have a Search Box web part configured for an internet search, set to output to an associated Search Results webpart, but when the page first loads the Search Results webpart throws an error.

If I enter a search query and hit enter everything then goes back to normal and the search works fine.

Does anyone know what might be causing the initial webpart to show an error when the page loads?

This is SharePoint Online.

Edit: Additional screenshot of Search Results webpart

Answer 1

It looks like you are not accounting for the possibility that the query is empty. When Bing receives an empty {searchTerms} string the query fails and throws that error.

Answer 2

Is this happening on a custom search center results page created by you or on default osssearchresultes page? If on a custom search center results page, do you have any customization on your search results webpart? If so check on the customization or post the details of what has been customized. If it is happening on default osssearchresults page raise a support ticket with Microsoft