Is there any particular reason you're trying to do this from the command-line as opposed to built-in features available in the UI? Also, might there be a system policy that's preventing you from performing these operations?

Here's a suggestion using the UI:

1. Open the Start Menu
2. In the Search Bar, type appwiz.cpl.
3. Wait for appwiz.cpl to appear in the search results. There should be only one entry at the top, under "Programs". It should have a document icon with some gears on it, and should be automatically highlighted.
4. With appwiz.cpl highlighted in the search results, press CTRL+SHIFT+ENTER. This will force Windows to attempt executing appwiz.cpl with Administrator privileges.
5. Respond to any UAC prompts as appropriate.

If the above does not work, there may be an issue with your system's Security Policy. Do the following to check:

1. Log into the system under an account that has Administrator permissions.
2. Press Win+R.
3. Type secpol.msc and hit ENTER.
4. Respond to any UAC prompts as appropriate.
5. In the left pane, navigate the tree to the following location:

   Security Settings\Local Policies\Security Options

6. Find the "User Account Control" options, near the bottom of the list.
7. Check the setting User Account Control: Behavior of the elevation prompt for standard users
   • If it is set to Automatically deny elevation requests, you will not be able to use Administrator permissions while running under a standard user account.
   • If this is set to any of the Prompt for credentials... settings, and the above process for running appwiz.cpl elevated still does not work for you, then you may have a different problem.

Try this:

runas.exe /savecred /user:administrator "%sysdrive%\testScripts\testscript1.ps1" 

It saves the password the first time and never asks again. Maybe when you change the administrator password you will be prompted again.

Windows 7 how to open Programs and Features from the run command