i have just opened a 2 month old drawing (in acad lt 2012) and all lines look as though they have been drawn with a crayon, any one advise on how to change this?

It looks like your line weight display is on.edwinprakoso2012-09-28 06:18:15

The toggle for it is located at the bottom of your screen in the Task Bar.  LINEWEIGHT On/Off

That fixed it Great.Many Thanks