Checando se esta conectado a internet

Function Tform1.IsConnected : Boolean;
var reg : TRegistry;
buff : dword;

begin
reg:= tregistry.Create ;
Reg.RootKey:=HKey_local_machine;
if reg.OpenKey('SystemCurrentControlSetServicesRemoteAccess',false) then
begin
reg.ReadBinaryData('Remote Connection',buff,sizeof(buff));
result := buff = 1;
reg.CloseKey ;
reg.Free ;
end;
end;