I need some help. Virus took over a laptop. I used Malware bytes and I was able to have it working fine, no issues. I put a flash drive to do a backup before something happened and I let it working while I went to bed. Around 4 am I woke up and went to check the backup and the laptop had a black screen saying: Missing Operating System. I did not think of anything besides the fact that it may have restarted and tried to boot from the flash drive, so I turned off the computer. Next morning the message was there and I could not get anywhere, even Vaio Recovery Center Tools would not work. I used Restore C: and Restore Complete System and I keep coming back to the same place, same message. Diagnosis and hard drive tests were all ok, no HD failure. I cannot make any sense of it, it feels like that my operating system vanishes by itself. It was working fine, no viruses and the backup progressing and working by itself. I did get some backup files in the flash drive and I can't tell if it is all of it. Now I cannot restore to factory setting unless I order the disks. What could have cause that if the virus have been taken out? Thank you. Computer: SONY VAIO PCG-3B2L Windows 7 Ultimate.