FULL PRODUCT VERSION :
java version "1.6.0_01"
Java(TM) SE Runtime Environment (build 1.6.0_01-b06)
Java HotSpot(TM) Client VM (build 1.6.0_01-b06, mixed mode, sharing)

ADDITIONAL OS VERSION INFORMATION :
Microsoft Windows XP [Version 5.1.2600]

A DESCRIPTION OF THE PROBLEM :
When the jnlp file is updated at the server, JWS fails to start the application the first time. "Unable to launch the application" message is shown instead. This happens with only some jnlp file contents, not all. At least <property> tags and os attributes in resources seem to have some impact. The effect of the content seems quite illogical, so there might be other tags and attributes effecting too.

The symptoms are exactly like in 6446676, which is reported to be fixed in mustang(b94).

STEPS TO FOLLOW TO REPRODUCE THE PROBLEM :
- download http://java.sun.com/products/javawebstart/apps/draw.jar to your web server to some directory
- save the following as draw.jnlp in the same directory:
-------------------------------------------------------------------------
<?xml version="1.0" encoding="utf-8"?>

<jnlp spec="0.2 1.0"
      codebase="http://server/path/"
      href="draw.jnlp">
   <information>
      <title>Draw 4 App</title>
      <vendor>Sun Microsystems, Inc.</vendor>
      <homepage href="http://java.sun.com/products/javawebstart/demos.html"/>
      <description>A minimalist drawing application along the lines of Illustrator</description>
      <description kind="short">Draw Demo Short Description</description>
      <icon href="images/draw.jpg"/>
      <offline-allowed/>
   </information>
   <resources os="Win">
      <property name="sun.java2d.noddraw" value="false"/>
      <j2se version="1.3+" href="http://java.sun.com/products/autodl/j2se"/>
      <j2se version="1.3+"/>
      <jar href="draw.jar" main="true" download="eager"/>
   </resources>
   <application-desc main-class="Draw"/>
</jnlp>
-------------------------------------------------------------------------
(note: change the codebase in this example to correct one)
- open draw.jnlp with browser -> draw app starts
- run command touch draw.jnlp in the server
- open draw.jnlp with browser

EXPECTED VERSUS ACTUAL BEHAVIOR :
EXPECTED -
Draw application starts
ACTUAL -
Unable to start application appears.

ERROR MESSAGES/STACK TRACES THAT OCCUR :
Details for "Unable to launch the application" message:
Exception:
CouldNotLoadArgumentException[ Could not load file/URL specified: D:\Documents and Settings\aa015037\Application Data\Sun\Java\Deployment\cache\6.0\59\1c52e23b-1084115d]
at com.sun.javaws.Main.launchApp(Unknown Source)
at com.sun.javaws.Main.continueInSecureThread(Unknown Source)
at com.sun.javaws.Main$1.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

Wrapped Exception:
java.io.FileNotFoundException: D:\Documents and Settings\aa015037\Application Data\Sun\Java\Deployment\cache\6.0\59\1c52e23b-1084115d (The system cannot find the file specified)
at java.io.FileInputStream.open(Native Method)
at java.io.FileInputStream.<init>(Unknown Source)
at java.io.FileInputStream.<init>(Unknown Source)
at com.sun.javaws.jnl.LaunchDescFactory.buildDescriptor(Unknown Source)
at com.sun.javaws.Main.launchApp(Unknown Source)
at com.sun.javaws.Main.continueInSecureThread(Unknown Source)
at com.sun.javaws.Main$1.run(Unknown Source)
at java.lang.Thread.run(Unknown Source)

Console:
Java Web Start 1.6.0_01
Using JRE version 1.6.0_01 Java HotSpot(TM) Client VM
User home directory = D:\Documents and Settings\aa015037
----------------------------------------------------
c: clear console window
f: finalize objects on finalization queue
g: garbage collect
h: display this help message
m: print memory usage
o: trigger logging
p: reload proxy configuration
q: hide console
r: reload policy configuration
s: dump system and deployment properties
t: dump thread list
v: dump thread stack
0-5: set trace level to <n>
----------------------------------------------------
#### Java Web Start Error:
#### Could not load file/URL specified: D:\Documents and Settings\aa015037\Application Data\Sun\Java\Deployment\cache\6.0\59\1c52e23b-1084115d


REPRODUCIBILITY :
This bug can be reproduced always.

CUSTOMER SUBMITTED WORKAROUND :
These changes seem to help with this demo draw app example:
- remove the <property> -tag
- remove os="Win" attribute from resource tag
- change os="Win" to os="Windows"