Platform: Windows 2000 Pro SP4 x86

Procedure:
1. Check that machine is clean of all previous Java installs.
 i.e.
no traces in Add/Remove
no C:/Program Files/JavaSoft
no Control Panel Plug-in
no java -version
no key [HKEY_CLASSES_ROOT\CLSID\{08B0E5C0-4FCB-11CF-AAA5-00401C608501}] in registry
no key [HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft] in registry.

2. Install 1.3.1_17 fcs and reboot
   Verify all above are correct.
3. Install 1.3.1_18b01 and reboot
   Verify all above checks are correct.

eg. registry
Windows Registry Editor Version 5.00

HKLM
----
[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft]

[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Plug-in]

[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Plug-in\1.3.1_17]
"JavaHome"="C:\\Program Files\\JavaSoft\\JRE\\1.3.1_17"
"UseJava2IExplorer"=dword:00000001

[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Plug-in\1.3.1_18]
"JavaHome"="C:\\Program Files\\JavaSoft\\JRE\\1.3.1_18"
"UseJava2IExplorer"=dword:00000001

[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Runtime Environment]
"CurrentVersion"="1.3"

[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Runtime Environment\1.3]
"JavaHome"="C:\\Program Files\\JavaSoft\\JRE\\1.3.1_18"
"MicroVersion"="1"
"RuntimeLib"="C:\\Program Files\\JavaSoft\\JRE\\1.3.1_18\\bin\\hotspot\\jvm.dll"

[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Runtime Environment\1.3.1_17]
"JavaHome"="C:\\Program Files\\JavaSoft\\JRE\\1.3.1_17"
"MicroVersion"="1"
"RuntimeLib"="C:\\Program Files\\JavaSoft\\JRE\\1.3.1_17\\bin\\hotspot\\jvm.dll"

[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Runtime Environment\1.3.1_18]
"JavaHome"="C:\\Program Files\\JavaSoft\\JRE\\1.3.1_18"
"MicroVersion"="1"
"RuntimeLib"="C:\\Program Files\\JavaSoft\\JRE\\1.3.1_18\\bin\\hotspot\\jvm.dll"


HKCR
----
Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\CLSID\{08B0E5C0-4FCB-11CF-AAA5-00401C608501}]

[HKEY_CLASSES_ROOT\CLSID\{08B0E5C0-4FCB-11CF-AAA5-00401C608501}\TreatAs]
@="{CAFEEFAC-0013-0001-0018-ABCDEFFEDCBB}"


4. Remove 1.3.1_18 and reboot.

Observe registry problems...

HKLM
----
Windows Registry Editor Version 5.00

[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft]

[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Plug-in]

[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Plug-in\1.3.1_17]
"JavaHome"="C:\\Program Files\\JavaSoft\\JRE\\1.3.1_17"
"UseJava2IExplorer"=dword:00000001

[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Runtime Environment]

[HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Runtime Environment\1.3.1_17]
"JavaHome"="C:\\Program Files\\JavaSoft\\JRE\\1.3.1_17"
"MicroVersion"="1"
"RuntimeLib"="C:\\Program Files\\JavaSoft\\JRE\\1.3.1_17\\bin\\hotspot\\jvm.dll"

i.e. the platform key [HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Java Runtime Environment\1.3] is now missing.


HKCR
----
Windows Registry Editor Version 5.00

[HKEY_CLASSES_ROOT\CLSID\{08B0E5C0-4FCB-11CF-AAA5-00401C608501}]

[HKEY_CLASSES_ROOT\CLSID\{08B0E5C0-4FCB-11CF-AAA5-00401C608501}\TreatAs]
@="{CAFEEFAC-0013-0001-0018-ABCDEFFEDCBB}"

i.e. the CLSID still references 1.3.1_18 even though that product has been removed.

Functionality wise:
- java -version returns java: not found
- attempt to load 1.3.1 applet from:
    http://java.sun.com/products/plugin/1.3.1_01a/demos/applets/Clock/example1.html
  fails
- Removal of 1.3.1_17 does not function (though I have not reproduced this problem on another win200pro box)
./java -version from installed directory and plugin control panel both function.


Note: I tested 1.3.1_02 over 1.3.1 fcs in same fashion.
Similar problems
- attempt to load 1.3.1 applet from:
    http://java.sun.com/products/plugin/1.3.1_01a/demos/applets/Clock/example1.html
  fails
- Removal of 1.3.1_02 works
- HKCR key is left pointing to 1.3.1_02
- java -version works fine (from any filesystem location) suggesting a minor long time regression.


Also tested 1.3.1_13 over 1.3.1_12.
Similar problems except in this case,
- java -version returns java: not found
- attempt to load 1.3.1 applet from:
    http://java.sun.com/products/plugin/1.3.1_01a/demos/applets/Clock/example1.html
  fails
- removal of 1.3.1_12 works
- HKCR key is left pointing to 1.3.1_13