Microsoft said on September 10 (opens in new tab) that its KB4515384 cumulative update fixed a problem that prevented search results from appearing in Windows Desktop Search. Windows Latest reported yesterday that Microsoft didn't actually resolve the issue, however, with numerous people complaining on Reddit and the Microsoft answer forum that search results still aren't showing up even after the update's installed.
This has become something of a trend for Windows 10 updates of late. Microsoft released an update to Surface devices in August, for example, that was supposed to improve Wi-Fi and Bluetooth performance. Instead, the update prevented those devices from connecting to 5 GHz networks. Now, an update meant to fix Windows Desktop Search has failed to resolve the problem for all of the affected users.
That isn't a good look. It's made even worse by the fact that Microsoft released the KB4515384 update to resolve high CPU usage issues caused by a problem with Windows Desktop Search. (And, by extension, the Cortana voice assistant.) Multiple users reported CPU usage as high as 40% for the SearchUI.exe process, but attempting to actually use Windows 10's search tool would only lead to a blank page.
Microsoft said in the knowledge base article for the KB4515384 (opens in new tab) cumulative update that it's not aware of any issues with the build. That seems unlikely, given the reports on social media that Windows Latest spotted, but it's possible Microsoft simply hasn't updated the article yet. We suspect it wants to make sure it can actually resolve the Windows Desktop Search issue before releasing another update.