My friend show me the error when he is trying to open the Facebook on his computer, the malware has blocked his Facebook account and he is not able to sign in, now the question is in my mind how the facebook know that the PC is infected from malware, so i start searching the finally i got answer that Facebook has invented his own security system and anti-malware application, which can run before user can processing for login.
And today we can show you how to resolve this issue, when you will get the error which can show in below image "Your computer needs to be cleaned"
When you get this error don't be afraid it is only alert by Facebook that your PC have infected form malware, and now you thinking to download the antivirus or maybe you already installed in your PC, it is not useful what type of antivirus you are using, you should download the anti-malware scanner while pressing in "Get Started" button, when you press this button executable file have start downloading.
(Don't close your browser as well facebook login page)
After download the executable file, right click and run as a "Administrator", if few second you will see the process will start in Facebook page.
It will take couple of minute to complete the process, after that you will surely able to login with your Facebook account.