Now you replace the suspicious/missing file.
Fortunately, there are several copies of the pci.sys file on your HDD in other places - you just have to boot on something to replace the missing file, then get rid of your afflicted antiwhatever software, consider something more friendly, use some different scanning software, then fix any remaining issues.
Once booted into the Recovery Console, from the C:\WINDOWS prompt enter:
copy c:\windows\system32\dllcache\pci.sys c:\windows\system32\drivers
Respond in the affirmative if asked to overwrite the existing file and then you should see a message that 1 file(s) was copied.
Type 'exit' to exit the Recovery Console and your system will reboot automatically.
This will not relieve your system of the malicious software or replace your potentially afflicted antimalware program though.
Do you really think suggestions that begin with the words try, might or maybe are going to be helpful?
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