No more than a few days have passed since the apparent leak of Longhorn 4015 to WiNBETA (not the web) and Neowin has learned of a possible new build, this time at build #4021. Our source who wants to be known only as Serpant_winalpha has also said that this will leak very soon.

as with 4015:
(Build 4021.main.030415-0745) DX 9 (9.0.900)
WMP 9 (2991), Windows Messenger 5
Media Player & Classic Tray (Quick Launch?), located on the sidebar.

We have 2 screenshots and 2 files for download, Neowin can't confirm if this is real or not. Longhorn is scheduled to enter Beta phase in or around the end of the summer so this build is still considered Alpha. There are improvements with WinFS and I'm told there is some exciting developments with Peer to Peer in Longhorn but thats all a surprise for later.

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