> does anybody how to encrypt XML? I want to save may applicaion setting using CURSORTOXML instead of registry.It is a good solution to encrypt the output file using encryption algo. or there is a shortcut? or alternative idea

As Christof said, I'd also suggest the Windows CryptoAPI. You have a good working sample with full source code in the FFC, accessible through the Task Pane-Samples or through the Component Gallery-FFC folder.

There is also my old article covering the basics at:
http://www.feldstein.net/CodeCryptoArticle.htm

Another suggestion if you want to save XML is to apply BASE64 conversion after you encrypt, using STRCONV(x,13)
http://msdn.microsoft.com/library/default.asp?url=/library/en-us/dv_foxhelp9/html/e2b743ac-dec7-43ae-82db-ba6fa1e2cbd9.asp

This way you'll be saving all printable 'safe' characters.

HTH