Visio Prof 2002 changes the reln reading arrow to "4"

I am using Visio 2002 (release 10.0.525) under XP to create UML Class Diagrams (which Visio call Static Structure Diagrams). I created several diagrams by adding class box shapes to the diagram and by attaching lines between the boxes to represent relationships/associations between the classes. If you double click on a line a properties window opens and you can set the "Name" & "Name Reading Direction" for the relationship. The latter feature adds a small arrow head on the left or right of the displayed name when you have the relationship name displayed on the diagram. (The name can be displayed or not by right clicking on the line, selecting the "Shape Display Options" menu then selecting "Name" under the "General Options"). My problem is this; after two days the small arrows suddenly started to show as "3" or "4" before and after the name respectively. And I cannot make them show as arrow heads again. I have sent the diagram to others and it has the same problem on their PCs. Does anyone have any idea how to get Visio to display the arrow heads again????

George Ludgate
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