When is it not safe to eat fresh mozzarella?

It is not safe to eat fresh mozzarella if it has been stored improperly, such as being left out at room temperature for more than two hours, or if it shows signs of spoilage, like an off smell, mold, or a slimy texture. Additionally, if the mozzarella is past its expiration date, it should be discarded. Always ensure that it has been kept refrigerated and is consumed within a reasonable timeframe after opening.