For non-bootable PCs, Kaspersky Rescue disk is my go-to resource. It is excellent at removing boot sector rootkits and other malware. The MS Defender offline scanner is good but not comparable to the Kaspersky Rescue Disk.
In my opinion, most of the software Jack recommends is rather ineffective. I do a lot of malware removal and use RogueKiller, MBAM , and TDSSKiller as the prime tools for most systems. Combofix is the next option if MBAM is not effective. Of course all those require a bootable PC.
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