How to change service accounts and service account passwords in SharePoint Server 2007 and in Windows SharePoint Services 3.0
If you want to reset Moss Service Account , Microsoft provides a good KB article on this. Refer http://support.microsoft.com/kb/934838 http://bytelab.blogspot.com/2008/11/changing-moss-service-accounts.html http://technet.microsoft.com/en-us/library/cc288991.aspx