Problem with program compiler. MT4 decides to compile most of my indicators but not all of them.

 
Sometimes when I compile a new indicator, MT4 decides to compile most of my indicators but not all of them. Some of my indicators do NOT appear in the Navigator window when this happens so I can't drag them onto a chart. Do you have any idea why this may happen?

I have to move some indicators into a different folder to get all of my indicators that start with "_TRO_" to compile and appear in the Navigator window. Could the "_" in front of the name be causing the problem?
 

How many files do you have in the /experts/indicators folder?

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