Help please!!!!!!!!! i using xp sp2 i installed pgm called custamized windows logon then my com cannot work?

NEVER install third party software unless you k now exactly what it does. Especially if it affects login. Much of it is junk. Since you have no pword, what on earth did you install this for? Unless you have a Windows domain server, you can NOT log into a domain. Unless it will log in against just your computer name and a blank pword, you may need to try it in safe mode. If this fails, you will probably need to re-install the system from scratch, losing ALL your files and programs. This will also disrupt the dual boot to Linux.