Open-sourcing Windows Live Movie Maker

Question

TLDR: Could Microsoft release all or part of the source code for Windows Live Movie Maker? I apologize if this is a weird place to ask. I just needed to choose a tag, and .NET seems to fit the least terribly, considering that the program is likely written in .NET considering Live Writer is.

In the past few years, Microsoft has released either all or portions of the source code of old and obsolete software under an open source license, for instance several versions of MS-DOS, 3D Movie Maker, and Windows Live Writer. I was wondering whether it would be possible for Microsoft to do something similar for Windows Live Movie Maker, which may fit the bill as software not currently marketed by Microsoft and potentially having limited-enough dependencies to be able to avoid code that Microsoft is unable to open-source. It doesn't necessarily have to be the whole thing. For instance, if there are libraries or API keys that would need to be excluded (like those used for getting music online or sharing the video via several services), that would be fine. I feel that would be nice to have this source code both for historical preservation and analysis.

If this is not possible, or there are limitations, I would be pleased to know the reasons (E.G proprietary external libraries, contracts, etc.)

Anyhow, thanks for your time and have a wonderful day. I apologize if this is more of one for a legal and/or engineering team.