Every time after startup, windows will stop responding after I click something. I tried using ctrl alt delete, but the screen would just turn black and give me a message saying "failure to display security and shut down options". Everything was fine with my desktop before and it's still new. Just bought it a few weeks ago. This started happening yesterday when I tried to add songs to this free mp3 player I got. The system said that the mp3 player malfunctioned and started making a sound, the sound that you hear when you repeatedly insert and remove a USB. I swear everything on my pc is legal and that there are no viruses. I tried scanning the pc in safe mode of any corrupted files and there was only one, but a message said that the file was fixed. Safe mode works fine though, I'm not sure why. I can't reformat the pc since I dont have the windows 7 disk. Acer didn't provide it in the box. I need help urgently. Thanks in advance.