Windows 10 build 9900

Windows 10 build 9900 is a build of Windows 10, leaked on 29th of January 2015.

It is the first leaked build of Windows to be compiled in the "fbl_awesome1501" lab.

Taskbar

 * The taskbar design has been changed to a flatter style and now uses the black color seen in the RTM.
 * Taskbar search has been improved with the addition of a text box.
 * Security and Maintenance icon on the taskbar has been removed.

Cortana

 * Cortana has been added.

Windowed Metro

 * The window design has changed to a more modern style.

PC Settings and the Control Panel

 * PC Settings has an updated homepage.
 * Update Center has been removed from Control Panel.

Charms Bar

 * Charms bar received a minor update.
 * Settings section has been removed from it.

UEFI BIOS
This build has to be installed on an UEFI BIOS, otherwise it will hang booting setup.

Window thumbnail color error
Window thumbnails on the taskbar do not change color, but the user can change it after the computer restarts.