Missing Startup Software

Hello,
While running "CCleaner", program found in the registry some missing. Here is exactly the line:
"Missing Startup Software "%ProgramFiles%\Windows Defender\MSACuiL.exe"HKLM\SOFTWARE\Microsoft\Windows\CurrentVersion\Run All users"
Made a search all over the system - no such file.
Windows defender works fine.
What is this file, why is it missing (should it be), where to find it.
System is newly upgraded to 1809 some days ago, and works fine.
Answers will be appreciated
Thanks
Motim

Motim said:

What is this file, why is it missing (should it be)...

Yes, it should be missing.

MSASCui.exe was the old Defender UI that was green and looked like the old Microsoft Security Essentials for W7. It was superseded by the Defender Security Center in 1703, though you could still open it if you knew where to find it. It was removed completely in later versions.

Bree said:

Yes, it should be missing.

Hello,Thanks for the answer.Mounted my previous 1803 Macrium image and there I found the file "MSASCuiL.exe".So my question is: If it should be missing, then why is it in the startup list of "TaskMgr" as on attached screenshot.Shall I remove this entry from the registry, or extract the file from above image and try to copy it into "Windows Defender" folder ? (will something break ?)Answers will be appreciated.ThanksMotim

1803 was the last version to include MSASCuiL.exe and MSASCui.exe, they were removed in 1809 and all later versions.

The purpose of MSASCuiL was to display the old Defender icon in the taskbar, while MSASCui was the old Defender UI.

Neither are needed (or will work) in 1809 or higher. In fact, attempting to run the old MSASCui.exe from 1803 in any recent version of W10 will now just open the Windows Defender Security Center.

If it should be missing, then why is it in the startup list of "TaskMgr"

A leftover for a previous version after updating it? It is not needed as your Startup list also has the item that's now used in place of MSASCuiL, the 'Windows Security notification icon'.

It is safe to delete the MSASCuiL startup entry from the registry (if that's where it is). It may not be a registry entry, it may be a shortcut in your %appdata%\Microsoft\Windows\Start Menu\Programs\Startup folder. Early versions of W10 did not show the taskbar Defender icon by default, it was common practice for users to put a shortcut there to make it show on the taskbar.

Bree said:

1803 was the last version to include MSASCuiL.exe and MSASCui.exe, they were removed in 1809 and all later versions.
It is safe to delete the MSASCuiL startup entry from the registry

Hello,
Thanks a lot.
Entry removed from registry.
Motim

You might prefer to use Autoruns to check / disable / delete such startup items