I want all my calendars in one place on my own hardware. My company uses Outlook and recently locked things down so API access or even simple caldav is restricted.
To get around this I created this powershell script that reads the info from the local Outlook process, converts it to JSON, then posts it to a configurable endpoint. In this case I use Node-RED to handle processing the sync.
It will only sync while the powershell script is running on your work machine. Being as there is no other decent alternative this is fine for me.
Hope someone finds this handy. I know my wife loves having all my calendars in one place.