Having installed the tcpip.sys from the hacked_files.zip doesn't solve my problem btw. So it must be other SP2 modifications which are the cause :-( I dont think rolling back to SP1 will be any real solution cause SP2 is needed because of all fixes included in it. I would much prefer to know what changed with respect to this error and just change that back to SP1 state. If anyone know anything please help cause it's driving me crazy.