getting user info with SPSite error

[Guest]

hellow my problem is i need to get the log in user information from the site
in the code. i tried this but i get this error "Cannot connect to the
configuration database."

SPSite site = new SPSite("http://sharepoint/BIP/default.aspx");
SPWeb web = site.OpenWeb();
string cadena = web.CurrentUser.LoginName;

any suggestions or possible error in my code??

thanks in advance.