What is meant by "system restore will not function" in the context of a malware infection?

The phrase "system restore will not function" in the context of a malware infection indicates that the system restore feature may be compromised by malware. Malicious software often targets system functionalities to maintain persistence or to avoid detection and removal. This can manifest as the system restore point being either corrupted or altered so that it does not revert the system to a previous, uninfected state.

When malware changes system restore settings or affects the stored restore points, users may be unable to effectively use the restore feature to revert their system's state. Therefore, even if a user attempts to use system restore to recover from the infection, the compromised nature of the restore points can lead to unsuccessful recovery efforts or even reinfection after restoration. This highlights the importance of keeping a clean backup in safe locations outside the infected system, as relying solely on system restore under such conditions may not effectively resolve the issue.