jnlp file won't launch on Windows XP - maybe due to permissions

When launching a .jnlp file it simply hangs saying checking for latest versions.

I suspect this is to do with lack of permissions or the wrong Java version. Any ideas?

The java version I am using is 1.4.2_09. The .jnlp looks for

<j2se initial-heap-size="64m" max-heap-size="128m" version="1.4"/>

However this should be ok shouldn't it?

Also, can anyone tell me every possible folder used on the C: drive by Java Web Start. I tried the demos on the sun site and they opened fine. They use version="1.3+"/

[622 byte] By [muppet_tizera] at [2007-11-26 15:49:06]