This is the error I received when trying to search in outlook 2016 : “Something went wrong and your search couldn’t be completed”
simple fix for computers running windows 10 and outlook 2016
1. CLOSE Outlook down completely
2. Click Start Button
3. Type “Index”
4. Select “Indexing Options”
5. Click Modify
6. Check the box beside “Microsoft Outlook”
7. Open Outlook and do a search.
(in my case to fix it I had to adjust step #7 since outlok was already selected and I had to remove the check click ok then select modify again and check outlook again)
more info here: http://answers.microsoft.com/en-us/office/forum/office_2016-outlook/something-went-wrong-and-your-search-couldnt-be/69a93e55-1b40-47cc-97ca-3c2f8204b69e?auth=1