How do I remove rootkits? Such as system modificated ones of high danger?

[Mo0nwalker]

So what should I do in the end? Should I just format the PC or should I wait as these are Rootkits that only Avast finds but none other programs (such as tdskiller etc) made especially to fight Rootkits ever finds? It doesnt sound right. 

[polonus]

Hi Mo0nwalker,

As only avast finds them, this could be due to changes made to the OS over time. If they are not vital for the functioning of that machine, I would keep them in the chest until later and go on. All that is in quarantine is "in shackles and cannot work any harm". "They sit there in limbo to ponder over their mischievous deeds", as to put it proverbially.
If nothing is found thereafter, then just do not give it another thought. Maybe you are overly focused on some non-vital temp or update files or files that cannot be properly scanned and therefore are flagged.
If interrogating computers and torturing enough for answers they are known to come up with all sort of random replies, just like witches in Inquisition days under torture. Same goes with av. Sometimes things are found to be solved by not longer giving it any attention,

polonus

[Mo0nwalker]

Avast doesnt allow them to be kept on the chest. Here is an attachment:
 
But I dont really care much about it these days, since only Avast finds them, and it always finds one or two and even none sometimes - with every hits being the same, different or nothing. Really annoying, inaccurate and so on, but I havent seen any bad signs happening on my pc so its fine. Only Avast, as I have tried about every possible programs designed to fight rootkits, finds these random system modificated rootkits which it cant put on the chest or delete, after all.