So, some days ago I played TF2 in the morning. By the aftetrnoon Steam didn't boot and I had to reinstall three or four times for it to boot. After that it ran fine and today it's not working again. It doesn't even appear when I boot the computer and I have not changed anything since yesterday. If I click a lot on the icon I can see the process or a very brief moment but then dissapears. I tried to reinstall and nothing happens. So, what can I do? This is driving me mad.