Seems to be an issue for very few saw post here was never resolved, just told to not worry about it.
http://www.eightforums.com/general-support/38173-task-manager-startup-blank-3.html
You check both these places in Registry and there were entries there ? HKCU\Microsoft\Windows\CurrentVersion\Run key as well as in HKLM\Software\Wow6432Node\Microsoft\Windows\CurrentVersion\Run key.
One Microsoft post stated list, similar to one i showed before......
For whatever reason the Task Manager no longer displays anything in the Startup tab.
I have since learned that this tab can be quite finicky. For example, deleting the StartUp folder from your local Programs directory can cause it to return empty.
I had deleted this folder:
C:\Users\[username]\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup
Once I restored the folder, the StartUp tab in Task Manager started working again.
I had this problem too. But, I managed to solve it.
I had deleted empty folders in my start menu. Apparently, not having a Startup folder in the Start Menu causes the new Task Manager to not show any startup items. Re-creating the empty Startup folder in my Start Menu made the other startup items reappear in the list for me.
So, make sure you have a Startup folder under Programs in both your personal start menu (default of "C:\Users\_username_\AppData\Roaming\Microsoft\Windows\Start Menu\Programs\Startup") and the all users one (default of "C:\ProgramData\Microsoft\Windows\Start Menu\Programs\Startup").
My only other thought as i read online was possible third party software causing this, can first try a clean boot see if they return...
Use MSCONFIG to do a clean boot...type msconfig in Run commmand
On the Services tab of the System Configuration dialog box, tap or click to select the Hide all Microsoft services check box, and then tap or click Disable all.
On the Startup tab of the System Configuration dialog box, tap or click Open Task Manager. On the Startup tab in Task Manager, for each startup item, select the item and then click Disable (here will not see anything, since was your issue).Close Task Manager.
On the Startup tab of the System Configuration dialog box, tap or click OK, and then restart the computer.