BDC accounts

Funny kinda problem happen i was installing new server on my network but as i didn`t find correct network adapter driver so i install it as workgroup though as BDC.after installing i found adapter driver & installed it -it welcomed me to new domain when i changed my domain name ,i can see server manager with all computer there but my user manager of domain is unaccessible & i can`t log in as a domain user though it let me in as local account which i establish during installion___any solutions with Thanks