I would like to start off saying this is my first time posting here and that my knowledge regarding this subject is sparse, mostly due to the fact that I just recently started to learn about this subject in detail right after I got infested, which happened on 19/4/18. So I would greatly appreciate it if things were explained to me in a simple and understandable way. I also need to add that I am not completely helpless at all, but I am definitely not an expert (which is why i need to consult real pros on this board). As I am writing this I am using my mother's laptop instead of my own PC.
Alright, I will begin describing my situation as best as I possibly can so that I can receive as much help at possible.
3 days ago I was infested with a virus that unleashed a large amount of mixed threats on my system. I quickly powered off my computer, booted it up again (this wasn't in safe-mode) and launched Malwarebytes. I did a threat scan and Malwarebytes managed to identify and remove 27 dangerous files, half of those were adware while the other half was Malware from the virus I downloaded. I went on the web and downloaded AVAST and did a normal scan through it. AVAST didnt find anything. Before I was planning to do a full system scan I was still fairly paranoid and sure that there are more remnants of the virus on my system, so I booted up Task Manager and looked at my processes which revealed that I had some suspicious processes running that I did not identify straight away. I searched up the suspicious processes and it was some sort of Spyware; the type that logs keystrokes and gathers info. I then did a full system scan with AVAST and it removed it together with some adware.
At that moment I thought I had removed all dangerous threats on my system, so I relaxed and played a videogame for some hours on my PC. The next day 2 days ago I booted up again and downloaded autoruns and process explorer in order to easier find and identify unrecognized and suspicious processes but I didnt find anything that I thought was malware. It was then that I went to "programs and functions" (my OS language is not English so sorry for any typos) and it was there that I found a program-file called WAHIVER.exe that was installed on my system the same day I got my virus infection... I panicked and tried to search the web for any information pertaining to WAHIVER.exe but I did not receive many results except from it being potentially a rootkit virus. I did not find any processes related to it either... So I thought that maybe it was a Rootkit. I couldnt find the location of WAHIVER.exe on my system files either... so I panicked and went into safemode and launched Malwarebytes and did a full system scan but it didnt find anything. I then tried to un-install WAHIVER through programs and functions but instead of a usual uninstall wizard saying "are you sure you want to uninstall" I instead got a default uninstall window with unintelligible gibberish text. I was kinda scared but I chose "yes" to uninstall it.... I was pretty sure that it wasn't really gone so I did a rootkit ONLY scan with Malwarebytes... but it didnt find anything.
So now I am certain that I have been infected with a rootkit virus and I have decided I wanted to restore my windows 7 to factory condition.(i am using a self-built computer btw).
Will a factory reset remove the rootkit? Are there any chances that my network has been somehow infested? Is it safe for me to transfer some videogames and small files over to an SSD or a USB without the fear of the rootkit being transferred as well? And my last worrying question: is there anything more I can do to remove the virus from my system once and for all?