Thanks Giovanni Montano
it works but with very small change, when i made the key Prefs, windows prompt that it already exist somewhere.
I found that it is here: HKEY_USERS\S-1-5-21-2986116552-1422457668-3418972334-1000\Software\JavaSoft\Prefs
but I made a key in the path you specified, and named it as 'prefs' not as 'Prefs'. [ all in small ]
It works and now I am not getting any warning.
here is the full story for Java HeadFirst Readers. It might help you in case you too got this warning :
Especially with Windows 7, the JVM has not by default the permission to write into the Windows registry where the backing store for java.util.prefs.preferences is located under MS-Windows.
When executing either the ReverseXSL transformer, or even the Regex tester program, one can get errors like: Could not open/create prefs root node Software\JavaSoft\Prefs at root 0x80000002. Windows RegCreateKeyEx
This does prevent registering a license. It does not prevent the software to perform transformations in the free software mode.
Fixing the issue is simply a matter of granting the necessary permissions to the registry root key at stake.
Run regedit.exe as administrator (regedit.exe is located in the c:\Windows operating system root directory).
Go to key HKEY_LOCAL_MACHINE\SOFTWARE\JavaSoft\Prefs.
Right click to set permissions. Check a mark in the Full Control check box for the user(s) that need executing the reverseXSL software.