::# Set Key File Variable:
    Set Key="id_rsa"

::# Remove Inheritance:
    Icacls %Key% /c /t /Inheritance:d

::# Set Ownership to Owner:
    :: # Key's within %UserProfile%:
         Icacls %Key% /c /t /Grant %UserName%:F

    :: # Key's outside of %UserProfile%:
         TakeOwn /F %Key%
         Icacls %Key% /c /t /Grant:r %UserName%:F

::# Remove All Users, except for Owner:
    Icacls %Key% /c /t /Remove:g "Authenticated Users" BUILTIN\Administrators BUILTIN Everyone System Users

::# Verify:
    Icacls %Key%

::# Remove Variable:
    set "Key="