unable to login

i removed a user from a domain that is no longer being used. i rebooted before adding him to the users while switching to a workgroup for a home network. the user said he was not given a passowrd to login without a domain. i was able to login as admin but couldt figure out how to get back to the domain login so he didnt lose his profile settings?
how would i get it bak up in his original profile???