Malware file ignored through ShieldNET
The Shield's Malware scanner identifies “code patterns” that “look” like malware. This has a huge advantage over other approaches: Shield is more likely to detect bespoke, and never-before-seen malware. If any code exists on your site, and it’s using common malware tricks, Shield will find it.
When Shield reports a file as being malware, and it actually isn’t, this is called a false positive.
When the Malware scanner identifies a false positive malware file, and each time you mark it as ignored in scan results...
... it sends that as a "false positive" signal to ShieldNET, so that in the future it probably won't be picked up on the scans.
You might receive email alert report that there is a malware file detected but there is nothing about that file in your activity log (file was not deleted automatically) and it isn't showing up in scan results either.
That means that you've probably already ignored it and that sent the signal to ShieldNET that a file was a false positive. It won't be picked up by the scan any longer.