Why won't xampp apache server load localhost on any port when control panel says it's running?
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I just downloaded the most recent copy of xampp.  I have been using this for some time.  However, today I cannot get anything to load from localhost.  The XAMPP control panel says it is running.  I have seen when another application has port 80 and I cannot get it to start. It will report busy.  That's not happening though.  

I did install ruby on rails last night.  I was following some online training with Lynda.com.  That is supposed to use Webbrick server on port 3000.  That doesn't work anyway.  
So, can anyone suggest what I should do?
Thanks,
Bruce