- (Microsoft) Active Accessibility (MSAA): https://en.wikipedia.org/wiki/Microsoft_Active_Accessibility
- Active Channel: https://en.wikipedia.org/wiki/Active_Channel
- ActiveX Data Objects (ADO): https://en.wikipedia.org/wiki/ActiveX_Data_Objects
- Active Desktop: https://en.wikipedia.org/wiki/Active_Desktop
- ActiveMovie: https://en.wikipedia.org/wiki/ActiveMovie
- Active Server Pages (ASP): https://en.wikipedia.org/wiki/Active_Server_Pages
- Active Setup: https://en.wikipedia.org/wiki/Active_Setup
- ActiveSync: https://en.wikipedia.org/wiki/ActiveSync
---
In particular at the time around Windows Vista, Microsoft named a lot of technologies "Windows ... Foundation", for example:
- Windows Communication Foundation (WCF)
- Windows Driver Foundation (today: Windows Driver Frameworks): https://en.wikipedia.org/w/index.php?title=Windows_Driver_Fr...
- Windows Identity Foundation
- Windows Presentation Foundation (WPF)
- Windows Workflow Foundation (WF)
---
Also the "Windows Media ..." branding was big for media technologies at the respective time:
- Windows Media Audio (WMA)
- Windows Media Center, Windows Media Connect (both abbreviated to WMC): https://en.wikipedia.org/wiki/Windows_Media_Connect
- (Windows) Media Center Extender (MCX): https://en.wikipedia.org/wiki/Windows_Media_Center_Extender
- Windows Media Device Manager: https://learn.microsoft.com/en-us/windows/win32/wmdm/windows...
- Windows Media DRM
- Windows Media Encoder (WME)
- Windows Media Player (WMP)
- Windows Media Services (WMS): https://en.wikipedia.org/wiki/Windows_Media_Services
- Windows Media Video (WMV)