Here’s a link to a .reg file to create the value.
Usual disclaimer: Use at your own risk. Backup your registry before making any changes.
This key/path may not exist.
Create {CB3D0F55-BC2C-4C1A-85ED-23ED75B5106B} (REG_SZ) at Computer\HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Shell Extensions\Blocked
Value data blank
Computer\HKEY_CURRENT_USER\SOFTWARE\Microsoft\Windows\CurrentVersion\Shell Extensions\Blocked
{CB3D0F55-BC2C-4C1A-85ED-23ED75B5106B}
Tip: You can copy and paste into the address bar in registry editor.