403 Forbidden on Sharepoint Central Administration after DCPROMO

I am using MOSS 2007 VPC image. I installed and then uninstalled active directory on the same server using “dcpromo”. Since then my sharepoint has been behaving strange. Earlier I received “Server Unavailable” error but resolved it by giving rights to “NT AUTHORITY\NETWORK SERVICE” account. Now I get a 403 forbidden error when I open my central administration on sharepoint and 404 page not found when I open on other sites in sharepoint.

This is driving me nuts…. any gurus please help !!!!!!!!!!!!!