two weeks ago i bought a s7 slim. It worked absolutely fine. But since day before yesterday i couldn't install some applications from the market. As i have noticed most of those applications were larger than, lets say 1Mb. But i still can install applications from hi space. Can anyone suggest what i should do?? And also USB tethering stopped working yesterday. I don't know why. It worked fine before that. Can this be a some kind of a virus attack?