Windows 10 1903: Microsoft's CPU spike fix breaks search on Start menu, desktop

Microsoft is looking into new Windows Desktop Search problems, caused by its latest Windows 10 1903 patch.

Microsoft's plan to split Windows 10 from shell is happening Windows 10 preview shows signs of Windows OS separating from the shell in line with Microsoft's modular plans.

Microsoft has had a bad run with Windows 10 version 1903 in the past month, leaving users wondering whether it's worth installing the latest security update or to wait for yet another fix.

The September Patch Tuesday security update also fixed the Windows 10 1903 Cortana CPU issues but has broken Windows Desktop Search, according to users. 

A string of bugs have occurred over the past month since the August 13 update KB4512508 for Windows 10 1903, which broke apps written in Visual Basic 6, VBA, and VBScript for all versions of Windows 10 back to Windows 7

SEE: 20 pro tips to make Windows 10 work the way you want (free PDF)    

A week later Microsoft patched this issue for all versions of Windows except Windows 10 1903, which finally got fixed in a separate update, KB4512941, on August 30.   

But KB4512941 also spawned reports from 1903 users that the Cortana process SearchUI.exe was causing severe CPU spikes, which Microsoft confirmed last week, promising a fix that arrived in the September Patch Tuesday update KB4515384 this week

As Microsoft noted on Tuesday, the high CPU usage from SearchUi.exe "issue only occurs on devices that have disabled searching the web using Windows Desktop Search". 

But whatever adjustments Microsoft made have caused more problems with Windows Desktop Search and the Start menu. The issue only affects Windows 10 1903. 

"Microsoft has received reports that some users are having issues related to the Start menu and Windows Desktop Search," Microsoft notes

The company is "presently investigating and will provide an update when more information is available".

Windows 10 1903 users on Reddit have complained that after installing the Patch Tuesday update, the Start Menu "results in a blank window again". 

Reddit users appear to be losing patience with Microsoft's ongoing Windows 10 fumbles. 

"Typical Microsoft, fixes the CPU usage by completely breaking search so it can't even be used," wrote another Windows 10 user. 

READ MORE: Microsoft is starting to auto-update Windows 10 Home, Pro users on 1803 or older to 1903

Microsoft is also drawing criticism on the Windows 10 Feedback Hub, where a user is recommending others against installing the security update, as per MSPoweruser

"KB4515384 should address an issue that causes high CPU usage from SearchUI.exe for a small number of users. But this update again introduces the same problem as the previous update. Part of the problem is a high CPU usage (~30%) and a totally broken search function. Currently, I see no other option than to blacklist this update also to prevent update to reinstall it again and again." 

Which brings users of Windows 10 1903 – the latest version of Windows 10 – back to the same predicament they were in a month ago. Should they install a security update with fixes for 17 critical flaws or wait for the next update that may or may not address bugs that break key Windows 10 features?  

At least one Windows watcher, Woody Leonhard, was rightly skeptical on Tuesday when noting that KB4515384 included an "apparent fix for the SearchUI.exe" bug.

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