The Windows XP and Windows Server 2003 source code that was leaked online last week on 4chan has been confirmed to be authentic after a YouTube user compiled the code into working operating systems.
Shortly after the leak occurred last week, ZDNet reached out to multiple current and former Microsoft software engineers to confirm the validity of the leaked files.
At the time, sources told ZDNet that from a summary review, the code appeared to be incomplete, but from the components they analyzed, the code appeared to be authentic.
NTDEV, a US-based IT technician behind the eponymous Twitter and YouTube accounts, was one of the millions of users who downloaded the code last week.
But rather than wait for an official statement from Microsoft that is likely to never come, NTDEV decided to compile the code and find out for themselves.
According to videos shared online, the amateur IT technician was successful in compiling the Windows XP code over the weekend, and Windows Server 2003 yesterday.
"Well, the reports were indeed true. It seems that there are some components missing, such as winlogon.exe and lots of drivers," NTDEV told ZDNet in an interview today, describing his work on XP.
NTDEV says these missing components mean that the leaked XP code is not yet in a fully usable state, such as for a "full OS replacement," but that the code is, nevertheless, authentic.
"Certain files, such as the kernel and the Explorer can be compiled easily. I have tried some programs from the compiled source of XP, and it seems that they are identical to the retail versions of Windows," NTDEV said.
Barring the missing components, NTDEV believes "the source can be used for compiling all the SKUs, as well as free (optimised) retail builds."
As for the leaked Windows Server 2003 source, the second major Windows OS version included in last week's leak, NTDEV said this code was also similar to the XP leak.
"The leaked source of Server 2003 is actually more complete than the XP one, but it lacks, just as the XP one, the Winlogon source code," they said.
"I presume this is due to the fact that it may contain the code to the activation process (just an assumption).
"However, unlike XP, I have managed to build a workable installation of [Server] 2003, but I had to substitute some files (Winlogon being the most important one, the rest of them being help files and drivers, mostly)," NTDEV said.
Still, last week's leak also included source code for several other Windows operating systems, such as Windows 2000, Embedded (CE 3, CE 4, CE 5, CE, 7), Windows NT (3.5 and 4), and MS-DOS (3.30 and 6.0).
NTDEV told ZDNet they already compiled the NT codebase earlier this year, when it first leaked online, and that they now plan to focus on compiling the MS-DOS 6.0 code next.