Drag-drop issue after update of Designer and VS2017(HRESULT: 0x800401E3 (MK_E_UNAVAILABLE))

Had an issue where I couldn't drag and drop an entity into the designer. Cropped up after updating EF Designer and then VS2017

Microsoft Visual Studio
---------------------------
An error occurred while performing the drop:

Operation unavailable (Exception from HRESULT: 0x800401E3 (MK_E_UNAVAILABLE))
---------------------------
OK   Help   
---------------------------

①developer prompt -> devenv /setup

②Right-click Toolbox -> Reset Toolbox

③Uninstalling extension, closing vstudio, opening vstudio, installing extension, restarting vstudio

Point 3 is usually what worked for me in the past (only happened one other time). But in this case, nothing worked.