Windows 10 Edge can’t be opened using the built-in administrator account

1. Run  secpol.msc 
2. Under Local Policies/Security Options navigate to “User Account Control Admin Approval Mode for the Built-in Administrator account“
3. Set the policy to Enabled

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System

• Create a DWORD value if it doesn’t already exist called FilterAdministratorToken
• Set the value to 1

Next we need to navigate to the registry and make an additional change:

• HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Policies\System\UIPI\
• Change the Default string key to 0x00000001(1)

Finally, restart Windows and then you will be able to enjoy Edge under your Built-in Administrator account.