His boss 'assured' him that he had her continued support. = His boss 'assured' him of her continued support. = “You have my continued support,” his boss 'assured' him.
You can 'rest assured' [=you can be sure] that these mistakes won't happen again. = 'Rest assured', these mistakes won't happen again.
They are not 'assured of' being paid. [=it is not certain that they will be paid]
(..) Yes. Miss Scott, are there any circumstances in which... the two of you... might be more than just good friends ? l hoped there would be, but no, l'm... assured there aren't. - But what would you say if-- - Sorry. Just the one question, please. No, it's all right. You were saying ? (..)1999 Notting Hill