Hello everyone. I a m a residential manager who is a salaried employee. My question is, is it legal to make a salaried employee work a company paid holiday for straight time?

Did you sign a contract? Was your job outlined? If it is within the bounds of your job then the answer is yes. That is what you signed on to. If it is outside the bounds of your job then you may be entitled to overtime depending on the State you live in.