I may sound dumb, but I went to a website to try and speed up my computer, and I did what it said and I think a couple of important files are missing. when I open Windows Explorer for the first time when I log on, it opans fine until about 30 seconds with it up and it crashes, I open it up again and it has to close straight away, and next time I go to open it up the window doesn't come up just, It Has Encountered A Problem And Has To Close. And also when I log-on, these winodws pop-ups come up with like log-on "something something" then it comes up again after I had to terminate the program and then I did it again and then my wallpaper comes up with nothing else, and to get everything to show, I go Ctrl+Alt+Del and then Add New Task... and just something random...
Can you guys help?