Because i am local admin and i’m authorized to do whatever i want, i can use process explorer.
But i want to use taskmgr.exe
The exe is signed by microsoft
That’s not a standard Windows prompt, looks like some third-party application is intercepting the call.
Check the registry:
HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows NT\CurrentVersion\Image File Execution Options- for a key named taskmgr.exe. If it exists, see if the taskmgr.exe key has a value called Debugger. If so, delete the Debugger value, or rename the taskmgr.exe key to e.g. taskmgr.exe.old.Then try launching Task Manager again.
If there’s nothing in the registry, you could monitor the process tree in Process Explorer and watch what happens when you execute taskmgr.exe. You could also use Process Monitor if you want to dig deeper and find out exactly what’s happening - you can filter out Microsoft processes to make it easier to see all thirdparty software interactions.