i have this message as a error when i try to sign on to sl i have no idea how to fix that ... i have updated pc, took off and redownload sl. restart pc .. this is the final thig it say invalid class string can anyone tell me how to fix this please thank you leave this here for others i fixed the problem you need to delete all of sl on your pc including your roaming an such take off sl and redload and then restart pc and and redown load good luck all