Windows 10 'Reset this PC' effective for removing malware?

Solution 1:

Per this document, Probably, provided you use the Reset option, and are not working with an instance that was upgraded from win8.

That said, there may be types of malware that may not be addressable in this fashion, depending on your system configuration. This is particularly true if you have partitions other than a system partition. Reset will not affect any partition other than the system disk.

Solution 2:

It does not appear that this feature is intended to be used to remove viruses, but rather as a shortcut to reset the PC to a factory state. This document explains the differences a bit. This should be effective for many types of viruses and malware, but you can't be 100% certain that something hasn't infected the recovery partition itself, where all the factory files are stored.

Using a removable recovery drive and storing it offline would avoid this problem to some extent.

Solution 3:

It depends where the malware has stored itself. It's probably better to just run effective virus protection programs (that's a whole different question) since they will catch your generic malware.

Regarding the reset itself, if the malware has infected your personal files, %appdata%, my documents, etc., then it could potentially propagate from the windows.old folder the reset will create.