Question: I have attempted to create a scheduled task to start the w32\_time task when I log on, since my windows installation - seems to want to ignore that real dst settings for my locale when I reboot - and I have to force a time update to get the clock right.

My user is an Admin user - and I can run the task manually from the an administrator command prompt.

In the scheduled task it has 'Run with highest privileges' set on - but the task fails with return code 2147943456 - which as far as I can tell means Access Denied; I am assuming this is due to a privelege issue.

This happens regardless of 'Run when user is logged on' is set or not.

If this matters; the task is scheduled to run when a user logs in.

Answer: 
An (untested) idea: Try making a shortcut icon to run the program, and have the shortcut icon run with UAC elevation; then have Task Scheduler run that shortcut.
I had the same problem trying to sync on startup. Looked everywhere. Eventually I learned enough to succeed, but not from any single source. I hope this will help those looking for answers.

* Run Task Scheduler as admin:

	+ right-click "taskschd.msc" in "C:\Windows\System32" and choose Run as Admin.
* Create basic task: in "Task Scheduler Library -> Microsoft -> Windows -> Time Synchronization"

	+ right-click to choose "Create Basic Task".
	+ Follow the instructions and choose what you intend to do: Start a program "C:\Windows\System32\w32tm.exe".
	+ Add arguments: "/resync" (without quotes, of course).
* In Properties of your created basic task:

	+ Choose "Change User or Group".
	+ Where it says "Enter the object name to select", type in "LOCAL SERVICE".
	+ It'll be changed to "nt authority/local service". Click OK.
	+ It'll be shown as "LOCAL SERVICE" just like other Windows 10 tasks.
	+ Check "whether user is logged on or not" and check "Run with highest privileges".
	+ Check Configure for: "Windows 10".This is how you run scheduled task as admin!
* Under Conditions, check "Start only if the following network connection is available: any connection".

	+ Check each tab to be sure they are configured the way you want.