Microsoft Store blocked 

0x800704EC

Try to enable Microsoft Store using Group Policy Editor:

gpedit.msc

 Navigate to the following path on its left sidebar.

Computer Configuration\Administrative Templates\Windows Components\Store

locate the policy Turn off the Store application. Put right click on it and select Edit.
If the setting is “Enabled“, then modify its feature to either Not Configured or Disabled. Finally, make a hit on the Apply as well OK buttons to confirm changes.

Re-register Store through PowerShell
Re-registering the Microsoft Store will most probably resolve Error Code 0x800704EC Microsoft Store is blocked

This workaround with PowerShell cmdlet is the next:

Get-AppXPackage -Name Microsoft.WindowsStore | Foreach {Add-AppxPackage -DisableDevelopmentMode -Register “$($_.InstallLocation)\AppXManifest.xml” -Verbose}

or