class UserAgent::Browsers::WindowsMediaPlayer

NSPlayer/12.00.9651.0000 WMFSDK/12.00.9651.0000
Windows Phone 8.1 (Podcasts app)::

NSPlayer/12.00.9841.0000 WMFSDK/12.00.9841.0000
Windows-Media-Player/12.0.9841.0
Windows 10 with Windows Media Player 12::

NSPlayer/12.00.9600.17031 WMFSDK/12.00.9600.17031
Windows 8.1 with Windows Media Player 12::

Windows-Media-Player/11.0.6002.18311
NSPlayer/11.0.6002.18049 WMFSDK/11.0
NSPlayer/11.0.6002.18005
NSPlayer/11.00.6002.18392 WMFSDK/11.00.6002.18392
Windows Vista with Windows Media Player 11::

Windows-Media-Player/11.0.5721.5262
NSPlayer/11.0.5721.5262 WMFSDK/11.0
NSPlayer/11.0.5721.5262
Windows XP with Windows Media Player 11::

Windows-Media-Player/10.00.00.3802
NSPlayer/10.0.0.3802 WMFSDK/10.0
NSPlayer/10.0.0.3802
Windows XP with Windows Media Player 10::

Windows-Media-Player/9.00.00.4503
NSPlayer/9.0.0.4503 WMFSDK/9.0
NSPlayer/9.0.0.4503
Windows XP with Windows Media Player 9::

NSPlayer/4.1.0.3936
Windows XP with Windows Media Player 6.4::

Windows-Media-Player/9.00.00.3367
NSPlayer/9.0.0.3270 WMFSDK/9.0
Windows 2000 with Windows Media Player 9.0::

NSPlayer/9.0.0.2980
NSPlayer/9.0.0.3270 WMFSDK/9.0
NSPlayer/9.0.0.3268 WMFSDK/9.0
NSPlayer/9.0.0.3268
Windows 2000 with Windows Media Player 7.1 (downgraded from WMP9)::

NSPlayer/4.1.0.3938
Windows 2000 with Windows Media Player 6.4::

NSPlayer/9.0.0.2980 WMFSDK/9.0
Windows-Media-Player/9.00.00.2980
Windows 98 SE with Windows Media Player 9.0::

NSPlayer/7.1.0.3055
Windows 98 SE with Windows Media Player 7.1::

NSPlayer/4.1.0.3925
NSPlayer/4.1.0.3857
Womdpws 98 SE with Windows Media Player 6.4::

NSPlayer/3.2.0.3564
Windows 98 SE with Windows Media Player 6.01::

NSPlayer/4.1.0.3857
Windows 95 with Windows Media Player 6.4::

User agents I have personally found:

Parses the Windows Media Player version to figure out the host OS version

def os
  # WMP 6.4
  if classic?
    case version.to_a[3]
    when 3564, 3925 then  "Windows 98"
    when 3857 then        "Windows 9x"
    when 3936 then        "Windows XP"
    when 3938 then        "Windows 2000"
    else "Windows"
    end
  # WMP 7/7.1
  elsif version.to_a[0] == 7
    case version.to_a[3]
    when 3055 then "Windows 98"
    else "Windows"
    end
  # WMP 8 was also known as "Windows Media Player for Windows XP"
  elsif version.to_a[0] == 8
    "Windows XP"
  # WMP 9/10
  elsif version.to_a[0] == 9 || version.to_a[0] == 10
    case version.to_a[3]
    when 2980 then              "Windows 98/2000"
    when 3268, 3367, 3270 then  "Windows 2000"
    when 3802, 4503 then        "Windows XP"
    else "Windows"
    end
  # WMP 11/12
  elsif version.to_a[0] == 11 || version.to_a[0] == 12
    case version.to_a[2]
    when 9841, 9858, 9860,
         9879 then              "Windows 10"
    when 9651 then              "Windows Phone 8.1"
    when 9600 then              "Windows 8.1"
    when 9200 then              "Windows 8"
    when 7600, 7601 then        "Windows 7"
    when 6000, 6001, 6002 then  "Windows Vista"
    when 5721 then              "Windows XP"
    else                        "Windows"
    end
  else
    "Windows"
  end
end