Well, my copy the led didn't light up when I gave it the specificed lighting current (20 mA). I remember when you exceeded the power of the lamps on the Elecronic's workbench, they went from illumination to dead, but that was 10 or 15 years ago since I played with it. As far as subhpoto's problem, till we establish what he did, we can't address the problem. Your first solution was to turn on the switch. I suspect he didn't insert the current limiting resistor based on his words, but this is an international forum where english might not be the primary language. I don't like to insert my words for their words, as it's the posters responsibility to provide enough information (like a schematic, screen shot, whatever) so the members can give them a coherent answer. Simulation software can simulate blowing components up.

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2. Electronics Simulation Software

If, and that's a big if, his setup was like I described, the led never lit. And it didn't energize when I inserted a 500 ohm resistor (slightly more than 20 mA flow). That is why I stated what I did. Can you show me a screen shot with the ideal led energized in Electronics Workbench 5.1.2?

I've inserted a 500 ohm resistor. And it does not change the diode(s), ideal, red, or green.

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Electronics Workbench 5.12 Free Download

Waste some of your precious time by blowing up a light bulb in Electronics workbench. It de-energizes and the filaments are open. LED's do not indicate they are on or off in version 5.12. Yes, I know to get rid of the error I shown on the screen required a resistor, even 1 milliohm works.

Electronics Simulation Software

With an unrealistic kA flowing. You, nor I, know if that was the OP's problem as they have not returned. If you can't prove the LED energizes under normal conditions, then state so.

I didn't consider it a waste of my time, nor beneath me, to ask the OP about his setup.