Disklavier

Yep, that jnlp stuff doesn't seem to be supported anymore (???)
Anyway,  if you go to:
http://10.0.1.15/prc/prc100.jar

your browser should prompt you for a location to save the prc100.jar file.
Once you put that somewhere, you should be able to construct the command line that I mentioned earlier, and actually run the virtual prc that way.  Running it via the jnlp file seems like a dead end nowadays.
      From: "jheitzeb1@... [disklavier]" <disklavier@yahoogroups.com>
 To: disklavier@yahoogroups.com 
 Sent: Saturday, October 10, 2015 1:35 PM
 Subject: Re: [disklavier] Mark IV virtual PRC with Windows 10 or El Capitan
   
    Kevin,  I have enclosed the code from my prcstart.jnlp file where 10.0.1.15 is corresponding IP address of my piano.  The other parameters seem to be the same as your code.  I have tried running this and it momentarily brings up Virtual PRC in menubar and then fades away to nothing.  When I get info on the file it is set to use "java web start.app(default).  Is there a way to run this script?  I do not see prc100.jar on my hard drive.  I am clueless.  Thanks Joan
<?xml version="1.0" encoding="UTF-8"?><jnlp spec="1.0+" codebase="http://10.0.1.15/prc" href="prc.php">  <information>    <title>Virtual PRC</title>    <vendor>YAMAHA</vendor>    <homepage href="./index.php" />      <description>Virtual PRC</description>      <description kind="short">Virtual PRC</description>  </information>  <update check="always" policy="always" />  <resources>    <j2se version="1.3+" />    <jar href="./prc100.jar" />  </resources>  <application-desc    main-class="gui.prc100" >    <argument>-h=10.0.1.15</argument>     <argument>-p=3191</argument>     <argument>webremote</argument>     <argument>-w= 31910</argument>   </application-desc> </jnlp>