Hi,
Thank you for your reply.
Yes, I did put the "aspnet_client/system_web/1_1_4322/WebUIValidation.js" under my application root. I also found that, for the pages right under my root, there was no problem for validation. The problem only happened for the pages under the sub directories of my application root. And also, if I install my web application with ultidev cassini on windows 2003, there is no problem of validation for all pages. The problem happened when I installed my web application on Windows XP PRO. I did not test it under Vista yet.
Please help. I spent a few days on it and have no clues
Thank you.
Albert