Windows 10 KB3156421 cumulative update makes many systems slow

By: Costea Lestoc
2 minute read

As many of you already know, in July 2016, Microsoft will release a big Anniversary Update for Windows 10. However, the developer is already preparing the Windows Insiders by releasing new builds packed with new improvements and features.

If you didn’t join the Insider Preview program yet and you are currently running the standard version of Windows 10, there is a cumulative update that has been released for this operating system. This update will bring your OS build to 10586.318, but a good amount of users who have installed it on their computers are claiming that it is causing some serious slowdowns.

Besides slow systems, Windows 10 users are also talking about “spinning dots after installing the update, computer either hangs or uninstalls the update.

Microsoft: Windows 10 update KB3156421 changelog (partial):

– A memory leak that was occurring when opening a portable document format (PDF) form multiple times has been fixed;
– An issue that was affecting Bluetooth functionality when a computer resumes from sleep has been fixed;
– An issue that was causing a recorded video to be lost when answering an incoming call has been fixed;
– Additional security issues with remote procedure calls, kernel mode drivers, Microsoft Edge, Windows Shell, Windows Journal, Virtual Secure Mode have been fixed;
– An issue that was causing the battery to be drained while the phone screen was off has been fixed.

If you’ve just updated your device and you have noticed that your computer is running very slow, you can try disabling Cortana and see if that solves the issue. Here are the steps that you need to follow in order to disable Cortana on your computer:

  • Click on the Cortana search box to bring up Cortana;
  • Click on the “Notebook” and then on Settings;
  • Now disable the “Cortana can give you suggestions, ideas, reminders, alert and more” feature by moving the slider to “Off”.

After disabling this feature, many users have already reported that their computers are running better. Have you installed the latest Windows 10 cumulative update on your computer? Is your computer running slow or you’ve never had this issue on your computer? You might wanna have a look at our previous article where we talk about some potential fixes for slow Windows 10 computers.

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