Rootkit

[Guest PeterG]

Hello, yesterday I got infected by a rootkit / RAT. 

What I did was instantly turn off PC, plug out the internet cable, and then got back on my PC, backed up my files on external HDD.

I have 3 disks, 2xSSD, 1xHDD in my computer. While I was still in Windows, I formatted the HDD.

Then I went into BIOS, and from there I formatted the both SSDs.

After that I booted Windows 10 installation USB, and installed Windows.

Then I have installed two antiviruses, one of them is ESET, and scanned my external HDD for any transferred viruses, from the time where I backed up my data on that HDD.

 

Is there any possibility there is still a virus on my PC?