this upload was brought to you by insomnia.

source:
- Original: https://web.archive.org/web/20090509082540/http://download.microsoft.com/download/8/C/6/8C620E1A-2A14-411F-A091-27AE6EDE0675/Windows6.1-KB958559-x64.msu
                    https://web.archive.org/web/20090510213409/http://download.microsoft.com/download/8/C/6/8C620E1A-2A14-411F-A091-27AE6EDE0675/Windows6.1-KB958559-x86.msu
- Refresh: https://archive.org/download/virtualpc-7/Windows6.1-KB958559-x86-RefreshPkg.msu
                   https://archive.org/download/virtualpc-7/Windows6.1-KB958559-x64-RefreshPkg.msu
language: multi (depends on the OS)
KB number: KB958559

File informations: (pulled from ZArchiver)
- Original x86
    + Filename: Windows6.1-KB958559-x86.msu
    + MD5 hash: 64cd57cc0304e94d55a65cc9fb8456f9
    + Size: 4.88MB (5121310B)
- Original x64:
    + Filename: Windows6.1-KB958559-x64.msu
    + Size: 5.66MB (5944612B)
    + MD5 hash: e33486f9dee630c15344d7b5ccae4607
- Refresh x86: 
    + Filename: Windows6.1-KB958559-x86-RefreshPkg.msu
    + Size: 15.32MB (16070039B)
    + MD5 hash: 73e9f082c9de33d681957dc82c761955
- Refresh x64
    + Filename: Windows6.1-KB958559-x64-RefreshPkg.msu
    + Size: 16.29MB (17091624B)
    + 0e7820bec8314beeddfd554b18855c39

more information can be found in:
https://betawiki.net/wiki/Windows_Virtual_PC

quick summary: this is microsoft's official VM platform bought from connectix.
it's used to install XP mode, but you can also use it to install later versions such as Vista or 7.
about why it has two variants: one is the original one, which predates 7's launch. i recommend using 
the refresh versions, as it might come with useful bugfixes and enhancements.

have fun installing!

⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⣿⡟⠈⠘⡅⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢠⣼⡟⠁⠀⠀⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⡽⠋⠀⠀⠀⡰⠇⠀⠀⠀⠀⠀⠀⠀⠀⠀⣀⣀⣄⣀⠀⢀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⠀⡰⢡⠞⠀⠀⠀⠀⣠⡏⠀⠀⠀⠀⠀⠀⠀⠀⠀⡾⠁⠀⠀⠀⠉⠉⠑⠠⣄⣀⠀⠄⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⡊⣠⠏⠀⠀⠀⣠⠞⠁⠀⠀⠀⠀⠀⠀⠀⠀⠀⢸⠁⣧⢣⡀⠀⠀⠀⠀⠀⠀⠀⢱⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠘⢱⣿⠀⠀⠴⢫⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⡞⠀⠻⡄⢱⢦⣤⣤⣤⡀⠀⠀⠀⢇⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⢠⢸⠏⢧⠠⠄⢸⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢰⡇⠀⠀⣍⣈⣿⡿⠿⣿⣿⣷⣔⠀⠘⡄⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⢸⠀⠀⡾⠀⠀⢸⡧⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢀⠇⠀⣸⠏⢹⣿⣷⡇⠈⠙⠉⠉⣷⠀⢸⡆⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⢰⠀⣿⠃⠀⠀⢸⡇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⣼⠀⠀⣿⠀⣻⣿⣿⡇⠀⠀⠀⠀⢹⠀⣬⢧⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠰⡐⣿⡀⠀⠀⣿⢅⡄⠀⠀⠀⠀⠀⠀⢀⣠⠞⠀⠀⢰⣿⣿⣿⣱⠟⠀⠀⠀⠠⠚⠀⠐⠃⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⣧⣘⣧⣰⣦⡿⠭⠽⠿⠜⠛⠚⠒⡼⠋⠀⢀⣠⣶⣿⣿⡿⠛⠁⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⠀⢾⡿⠿⣧⣿⡧⠀⠀⠀⠀⠀⠀⣠⡅⣠⣾⠿⣻⣿⠛⠉⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⢀⡔⠋⠀⠀⠙⠒⠃⠀⠀⠀⠀⠀⠰⣻⣿⣿⣿⠞⠁⠀⠓⣆⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⣠⠎⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⢄⠀⠀⠀⠉⠉⠁⠀⠀⠀⠀⠈⢆⠱⡀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⡰⠁⠀⠀⠀⠀⠀⠀⢺⡄⠀⠀⠡⠈⡆⠄⢡⣘⡆⠀⠄⠀⠀⠀⠀⠈⣟⠂⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⣲⠃⡄⠀⠀⠀⡄⠀⢸⡎⠘⡀⠠⠤⡒⣃⣟⠉⠁⠘⠀⠸⠀⠀⠀⠀⠢⡈⠌⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠠⢠⠇⣼⠀⠀⠀⠀⡇⠠⢸⡇⠀⣧⣰⡰⠔⢎⣡⣤⣀⣐⡃⠀⡅⠠⠀⠀⠀⢣⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⢸⢠⢿⠀⡀⠀⠀⠀⢠⠘⠇⠀⠙⠁⢀⡴⠋⠁⠀⠈⢛⢆⠀⡇⠀⡄⢰⠀⢸⢆⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⢠⢸⠇⠸⠀⢣⠀⠀⢠⡸⡟⠒⠄⠀⠀⠈⠀⠀⠀⠐⠋⠁⡎⠀⣿⠀⡇⢸⠀⠸⣼⡄⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠈⠎⠀⠀⠰⠈⢦⠀⠀⢹⡓⠒⠲⠀⠀⠀⡠⠀⠀⠀⠀⢰⠃⠀⡏⠀⡇⢸⠀⠀⡯⠁⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⢠⢈⡆⠀⠀⡟⣄⠀⠀⠐⠁⠀⠀⠀⢀⡠⢿⠀⠀⡇⠀⡅⡼⠀⠀⢇⠠⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⢙⡗⠀⠀⠀⠈⡍⠒⠢⠤⢤⡴⠚⠉⢀⡜⠀⢠⣅⣀⠃⠁⠀⠀⠈⢇⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⠀⣾⠀⠀⠀⠀⠀⠁⡰⠊⢱⠋⠁⢀⡠⠚⢀⠀⣼⣤⡈⢳⣤⡀⠀⠀⠈⠳⡄⠀⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⠀⣰⠃⠀⠀⠀⢀⡴⣿⠁⠀⣸⡦⠘⠁⠀⠀⣸⢠⣿⣿⣴⣾⣿⣿⢦⠀⠀⠀⠸⡄⠀⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⠀⢀⠎⠀⠀⠀⠘⣯⠀⡼⢠⡎⠉⡇⠀⣀⢴⢾⠁⢸⣿⣿⣿⣿⣿⣿⣿⣷⠀⠀⠀⠈⢦⠀⠀⠀⠀⠀⠀⠀⠀
⠀⠀⠀⠀⢠⠊⠀⠀⠀⢰⣼⠟⣷⡇⢸⣇⣠⣧⠚⣱⠃⣿⠀⣾⣿⣿⣿⣿⣿⡿⣻⣿⡆⠀⠀⠀⠀⠱⣄⠀⠀⠀⠀⠀⠀
⠀⠀⠀⢠⠃⠀⠀⠀⢠⢻⣏⣤⣹⡧⠚⠛⡷⠀⢠⣣⡞⠻⠀⣿⣿⣿⣿⣿⣿⢳⣿⣿⣿⡀⠀⢀⠀⠀⠘⢤⠀⠀⠀⠀⠀
⠀⡠⠰⠃⠀⠀⠀⢀⣾⣾⣿⣿⣿⡇⠀⢀⡇⡰⢣⣷⣤⣴⠀⣿⣿⣿⣿⣿⣿⣿⣿⣿⣷⢷⡀⠀⢆⠀⠀⠀⠑⢤⠀⠀⠀
⢠⠃⠀⠀⠀⠀⠀⡜⣼⣿⣿⣿⣿⣷⡴⠋⣀⣼⣿⣿⡟⠛⠀⠟⠿⢿⣿⣿⣿⣿⣿⣿⣿⡟⣷⠀⠈⠆⠀⠀⠀⢌⠱⡐⢄
⢸⠀⠀⠀⠀⠀⠠⣷⣿⣿⣿⣿⣿⣥⣴⣾⣿⣿⠟⠻⣷⣶⣶⣤⣤⣿⣿⣿⣿⣿⣿⣿⣿⣿⢿⠀⠀⠈⠄⠠⠀⠀⢦⠑⢾

my self-insert touhou roleplay (ignore this):
diary: day 1 on gensokyo 
hi, i am sanae, a schoolgirl from the outside world. i'm currently being a miko right now.
i would say, this place is fun, and i can even show my creative bullet patterns to amaze my friends!

oh wait, i have a date with reimu-san now. see you later!


self-insert author notes (ignore this too):
today i meet new friends, it was fun. though my demise is near, i don't even know what should i do at this point.
it's a single chance; if i miss, my life would be over.

for those who have an exam/test: sleep well, maintain a good health and don't be sleepless like me. 
wish you all best luck.