Emergency UNIX and Linux Support

I would rename the users home directory and then make a new one for them Gnome and their applications should generate default configuration files when they login and launch their applications. Just make sure to copy all their documents to their new home directory. Then you can create a new user and attach it to the user in questions old home directory to isolate the problem so you have a better fix next time this happens.

I have taken a complete tar of my Home dir ,but i don't know how to rename Home dir can you suggest me

Code:

#cd /home
#mv homedir newname
#mkdir homedir

By doing this when i untar my backup inside the new homedir will it replace all the default file isn't it ,so wouldn't i ended up in the same thing isn't it ,just clear the doubt if you could

When you made the tar of your home directory did you use the relative or absolute path? Since all you are doing is renaming it, you don't really need to tar it up. Assuming the problem is in the home directory, you can just copy or move all of the non-config files to the new directory.