FileASSIN is a well known malware tool which has been designed by hackers with two goals in mind. The first goal is to try and get your personal details (name, address, phone number etc) from your hard drive and use this information to carry out other attacks. The second is to try and load itself up onto your windows system as a Trojan and pretend to be an operating system program. This way it can then infect your system, delete any system files such as the likes of dll, settings and so forth, and has the potential to spread further to other computers on the network if you are not careful. The really great thing about this particular virus is that it's able to infect not only windows PCs but also Macs (through a fake email attachment) and even Linux machines. This means that if you want to get rid of this virus, you need to be able to remove all parts of it, and not just the symptoms which have caused your problems.
To remove fileassassin, you need to be able to use a program called "MalwareBytes" which is able to scan through your PC and fix all of the infected parts of this virus. This virus works by installing itself onto your windows operating system, changing some of the files & settings on your computer, and then working its way into all the core system files on your PC. From there, it will change various components of your system (depending on what type of virus it is) and then carry out its desired task. For example, one particular thing it will do is remove various important system files that Windows requires to run. To ensure you don't have this infection on your PC, you should download a reliable anti-malware program such as Malwarebytes and let it perform a full system scan.
After using the program, if you find that it cannot remove the virus, then it's then advisable that you use a 'registry cleaner' to clean through your PC and fix any of the damaged / corrupted settings that were left by the malware application. One effective way of removing fileassassin is using a registry cleaner tool, which can scan through your PC and fix the various settings that the FileASSIN had placed on your system. You can use these programs by downloading one from the Internet and then letting it fix all the damaged files that the virus left behind. These tools are normally very effective and can make sure that you have the security and reliability you need on your PC.