Hi Kousy
With the standard express vi you can't do this. So here are the steps how you can do it:
1. Place the express vi on the block diagram and configure it as needed
2. Right-click it and select "open front panel"
3. In the following dialog select convert -> now it is a normal sub-vi
4. Right-click the string-control and select "Password display"
5. Save the vi
Now it should work.
Hope this helps.
Thomas
Using LV8.0
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