We have this issue lately, when we open up a saved drawing, in BOM and rev tables notes all was saved with the lines but when someone opens it, the lines disappears like in the below picture. even tho you can see the lines when it is loading the drawing. Ones drawing is updated, it's all gone. we can bring it back by clicking the table and change the line thickness from none to min thickness. We want to know what causing this so we can fix the problem for everybody. 

this screen shot taken when the drawing was being loaded

this is after loaded.