Barely 24 hours after the launch of Windows 10 Build 10158, Microsoft follows it up with the release of Build 10159, which fixes over 300 bugs.

On Tuesday, June 30, Microsoft took the wraps off the new build for its Fast ring users in its Windows Insider Program. "Insiders" who are included in the Fast ring receive updates first, but they also encounter more bugs in fresh releases.

"We have something of a surprise for you today! Our last build to the Windows Insider Fast ring was just yesterday, but we're following it up with another build today—Build 10159, releasing to the Fast ring," stated Microsoft.

The blog post reports that the new build does not include a gamut of new features but brings in fixes and a mysterious "very interesting change."

Other reports suggest that the new change is the redesign of the actual login screen, which puts the user's image in a translucent panel over the desktop picture. This is a notable feature when compared to the previous build, which placed the user's photo on one side of their name, Microsoft account email and password field.

The new build also comes with a new default wallpaper, which Microsoft showed off last week. A light shines through the Windows logo in the latest wallpaper.

Users who are downloading Windows 10 Build 10158 may get an error code "0x80246017" once Build 10159 has been published.

In the event this error message shows up, users are advised to reboot their system and check for current updates to get the latest Windows build. However, it is a rare case scenario that customers will receive the error since the company has stopped providing the previous Windows build to users who have not already updated.

It is uncommon to find an update in such a short span of time as what Microsoft has done now; however, such a process undoubtedly aids the company in evaluating its builds.

Microsoft usually pushes out a new software build to its internal employees before rolling it out to testers, and this process can take a couple of days. Ideally, Windows Build 10158 should have cleared the tests before Microsoft started evaluating Windows Build 10159 and pushed the former out hastily.

Members of the Fast ring using Build 10130 can now upgrade to Build 10159.