NWA logon problem

We just completed the System copy process of XI from XDV to XQA. After that, i'm getting the following problem to logon to nwa.

even after entering valid user ID & password we are getting the same login page with the User ID field filled and password field empty, without showing any error messages. If we enter incorrect user ID or password it says "user authentication failed". This is happening for all valid user IDs (even for super administrator).

In following link, nwa and user management is not working. I'm not able

to logon. It failed with user authentication problem.

http://server:port/index.html

but using the same user ID and passowrd, i'm able to logon to the following link:

http://server:port/sld

Regards

Amar