Error When Placing A New Order By Admin

Hi,

I am getting an error when I place a new order (placed by admin).

"ErrorOrder was not placed"

This happened just after upgrading to 4.7.3

Any idea how to resolve this please?

Try to temporary disable 3rd party modules. As far as I can see there is a hook in the fn_place_order which can be used to allow or disallow order placement