Microsoft has released the second cumulative update KB4100403 for Windows 10 April 2018 Update in May. The first update is KB4103721. After installing this update, the build number of Windows will become 10.0.17134.81.
You can check for your current Windows version and build by going to Run –> winver.
It seems that Microsoft has pushed this update in a hurry because a lot of issues that need to be fixed in Windows 10 Version 1803 are still not fixed in this update.
There are only 6 fixes included in this update. Here’s the list:
Fixed an issue with web worker issue in Internet Explorer
Fixed time zone issue which was also fixed in the latest updates for Version 1709 and Version 1703.
Fixed an issue with Microsoft Edge and other applications hanging when creating a new audio endpoint or starting video playback.
Fixed Windows Hello enrollment issue with dGPUs.
Fixed a power issue where Windows was causing major battery drains on systems with NVMe devices.
Fixed an issue where closed-caption settings are preserved after upgrade.
Known issues after installing KB4100403 update
Microsoft has listed two known issues which are not fixed in this update. Both the issues are related to hard drive compatibility. Windows 10 Version 1803 is still not compatible with Intel SSD Pro 600p and Toshiba XG4, XG5 and BG3.
If you are using these hard drives, you are advised not to upgrade to Version 1803 until Microsoft provides a solution to this problem.