Windows Vista build 5048

Windows "Longhorn" build 5048 (with a build tag of 5048.winmain idx02.050401-0536) is the first Omega-13 build of Windows Vista to leak after the development reset of Windows "Longhorn". It was released to attendants of WinHEC 2005, and was known as the "Longhorn Developer Preview".

This pre-beta build introduces the Aero theme that would become a part of Vista. It has a new wallpaper and some very Vista-like interface areas. Windows Media Player 10 and Internet Explorer 6 SP2 are also now present.

This build features the Windows Aero theme and visual effects. Reportedly, there is a limit of 50 files per folder imposed, but it can be bypassed by viewing icons in groups.

While Microsoft had made a significant amount of progess in reinstating "Longhorn" features, many were surprised that this and similar builds more closely resembled Windows XP and Windows Server 2003. Technology blogger and Windows enthusiast Paul Thurrott once stated:

"'My thoughts are not positive, not positive at all. This is a painful build to have to deal with after a year of waiting, a step back in some ways. I hope Microsoft has surprises up their sleeves. This has the makings of a train wreck.'"

This build includes DWM, but it can crash when starting. Betaarchive user ovctvct wrote a tutorial on how to enable DWM without any crash. It calls itself Beta 1 in the setup handle, but is not true Beta 1.