IcedTea-Web not able to retrieve file from cache on Windows

Issue

• javaws application fails to launch with the following exception in javaws_last_log.txt:

java.io.IOException: java.lang.NullPointerException: name can't be null
        at net.sourceforge.jnlp.JNLPFile.openURL(JNLPFile.java:318)
        at net.sourceforge.jnlp.JNLPFile.<init>(JNLPFile.java:231)
        at net.sourceforge.jnlp.JNLPFile.<init>(JNLPFile.java:215)
        at net.sourceforge.jnlp.JNLPFile.<init>(JNLPFile.java:265)
        at net.sourceforge.jnlp.runtime.JNLPClassLoader.getInstance(JNLPClassLoader.java:544)
        at net.sourceforge.jnlp.runtime.JNLPClassLoader.initializeExtensions(JNLPClassLoader.java:579)
        at net.sourceforge.jnlp.runtime.JNLPClassLoader.<init>(JNLPClassLoader.java:336)
        at net.sourceforge.jnlp.runtime.JNLPClassLoader.createInstance(JNLPClassLoader.java:422)
        at net.sourceforge.jnlp.runtime.JNLPClassLoader.getInstance(JNLPClassLoader.java:496)
        at net.sourceforge.jnlp.runtime.JNLPClassLoader.getInstance(JNLPClassLoader.java:469)
        at net.sourceforge.jnlp.Launcher.createApplet(Launcher.java:736)
        at net.sourceforge.jnlp.Launcher.launchApplet(Launcher.java:660)
        at net.sourceforge.jnlp.Launcher$TgThread.run(Launcher.java:953)
Caused by: java.lang.NullPointerException: name can't be null
        at java.io.FilePermission.init(FilePermission.java:209)
        at java.io.FilePermission.<init>(FilePermission.java:310)
        at java.lang.SecurityManager.checkRead(SecurityManager.java:888)
        at java.io.FileInputStream.<init>(FileInputStream.java:127)
        at net.sourceforge

• The javaws application works the first time after rebooting Windows.
• The javaws application works on other boxes.