Windows Task Scheduler Custom Handler

Question

From Windows Task Scheduler within the Actions tab on some scheduled tasks there are values of Custom Handler assigned to the Action attribute.

Question

• Is there a way to see custom handler details since an error pops up through Task Scheduler?

  This type of action cannot be edited in this tool

Example Task with Custom Handler

\Microsoft\Windows\.NET Framework\.NET Framework NGEN v4.0.30319

Solution

What exactly is the Task Scheduler "custom handler" from the Actions tab?

These are system tasks and you can run the schtasks commands accordingly and search the registry to get more detail (see below quoted text and references).

Warning: You probably could make adjustments to system tasks by manipulating the registry or finding another [hack] forceful to do it, but these are not meant to be modified by users since they are systems tasks so you may hose something up with Windows change these.

You can't view Custom Handlers or Custom Triggers because there's nothing to view. They're compiled code, in DLL's. They implement the interfaces defined in the task scheduler API, these are found here:

Task Scheduler Interfaces (Windows)

You can see which DLL is called by viewing the Task definition. For example, Badge Update, notice the source is WinStoreUI.dll:

schtasks /query /XML /TN "\Microsoft\Windows\WS\Badge Update"

---

Because you don't need to edit it. This is not a user task, but a system task. You can export the task to XML, find the handler GUID, search regedit for it, etc, etc, but editing it still won't make sense.

If you want to edit, delete the task and import the modified XML. Still doesn't make sense, but perhaps it would satisfy those who insist on editing such tasks. I doubt, though

_source

---

Further Resources

• schtasks

Comments

[Admin]

So basically, if i get it right, those handlers or triggers are "hard coded"? Whenever they are introduced to system there are no way to be manipulated by user, even by administator.

[Vomit IT - Chunky Mess Style]

That appears to be the case since these are systems tasks but run the schtasks command accordingly and search the registry to get more detail. You probably could make adjustments by manipulating the registry or finding some other forceful way to do it (like a hack) but these aren't meant to be modified by users since they are systems tasks so you may hose something up with Windows if you do make changes to them.\

[Admin]

Thanks for the comment, seems like there is need for 'extereme measures' to deal with system tasks. Case closed.