Windows 8 build 8102.101

Windows 8 build 8102.101 is the official Developer Preview build of Windows 8. This build is the first released build to have a fully functional Start screen, and also have Charms out of the box and an updated BSOD. It was shown to the public on 2011-09-13.

Redpill
This build was the first build released to the public to have all new Metro features working out of the box. While the image that was distributed by Microsoft has all Metro features enabled, internally it still uses the same mechanism of (un)locking Metro features through Redpill as seen in earlier builds. A remnant of the application of Redpill is present in this build in the form of a 'redpill.log' file in the System32 directory. This file gives some insight into the application of Redpill. Contents of the file:

 Running with /labuseonly Running with /restrictedlab Running with /privatebinary Overriding version check... Installing licenses... Setting IE activesetup stub Setting MIE install state... Checking MIE package state... Restarting sessionenv... Setting IE activesetup stub ERROR: Binary version mismatch! Enabling via /enable Setting MIE install state... Checking MIE package state... Preparing to install immersive browser... Installing MIE OOB... Installing MIE complete. Return code: 0 Finished installing MIE OOB. Restarting sessionenv... Setting IE activesetup stub NoExplorer flag set; skipping explorer restart

Because of the similarities in the way of how features are locked between 8102 and some earlier builds, the files dropped by Redpill in build 8102 have been used to unlock Metro features in several older builds, such as builds 8056, 7989, and 7927.

Disabling Metro
As this build still utilizes Redpill, setting HKCU\Software\Microsoft\Windows\CurrentVersion\Explorer\RPEnabled to 0 will disable the Metro features like the start screen or hot-corners, effectively un-redpilling the build and resulting in an experience similar to earlier leaked builds of Windows 8, and thus Windows 7, after Explorer is restarted. Special applications were created to suffice for this need. Note that setting RPEnabled to 0 will also result in the Microsoft Confidential watermark appearing on the desktop, just like in earlier leaked builds of Windows 8. In cases where Explorer was not restarted after disabling Metro, a hybrid between classic and Metro may occur where part of the Metro interface still shows on top of the classic shell.

Removed features
Despite being the first build to come unlocked by default, some features have been removed in this build. Those include accent colors and the ability to zoom out of the start screen.

Timebomb update
This build was originally set to expire on 2012-03-11, but Microsoft released KB2671501 for both this build and its server counterpart to extend the expiration date to 2013-01-15.

Aero
With Aero enabled, the lower half of the window background of some applications which uses Aero, like Desktop Gadget Gallery or Mozilla Firefox, have a grey square.