I have a domain controller having 40 clients MS Exchange is also Installed .Domain controller is causing few problems so i want to format it and start fro scratch is there any posibility thati can take the backup of users name and there password so this experiment will remain transpirent from client side i can install new domain and active directory and import users so when they will log there PC on in the morning the will not face any problem and is it possible that if i can keep the domain name same the profile of user which is not roaming will not change Love Gnome!

a domain users sid is a combo of domain and user sid. New domain, even of the same name, means different domain sid. solution is to bring up another DC so you preserve your AD schema, DNS and users. You can use an available workstation. Then rebuild the server. Give a person a fish, they eat for a day. Suggest they internet search and they learn a skill for a lifetime.

You can take your domain backup means username and password,Group and OU In System State Date Backup.

not without getting the same errors when you restore the dammaged DB. why not just fix the problem, i have yet to come across a AD problem thats not fixable