Log File : very strange and Interaction with Windows Defender

Avast Free Antivirus / Premium Security
1

Hi,

I have a question about Avast log file. On 17th February, I formatted my disk c: partition because I had a virus. I reinstalled Windows and Avast on 17th February.

Today, I saw in log files That Avast is mentionning an event related to 16th February. I don’t understand How Avast can keep trace of event on 16th of February While I formatted my disk and reinstall all my applications on 17th.

I have another Question :

Today, I launched a full scan with Windows defender and Avast Detected a virus in D/System volume information_restore. I would like to know why Avast detected the virus when Windows Defender was scanning thi area and did not detected it before ?

Thanks a lot for your help for these two questions.

Best regards

2

Is your clock set correctly?

Avast! is an antivirus program while Defender is antispyware. They are designed to find different things.

3

Thanks for your answer.

No problem with my clock.

I know about the difference between AV and Antispyware software, but I don’t understand why scanning with Windows defender my disk with files (that where certainly contaminded before) has launched the detection of this virus by Avast.

Thanks

4

The only way to remove a virus/infected restore point is to disable system restore and reboot. Once you have done that ALL restore points will be cleared (windows doesn’t allow for selective deletion of restore points in the System volume information folder, a protected area), scan your system again and if clear enable system restore again and reboot, this will create an initial restore point.

If you have windows defender do an on-demand scan and avast’s standard shield it active any file that defender opens will also be scanned by avast and can cause this type of thing. If I’m running any other security scan I pause standard shield, this reduces, the possibility of conflict (as they fight for control), the duplicate scanning of files and will reduce the overall time taken for the primary scan.

5

Isn’t it the date of the problematic file?

System restore is a folder that could contain some ‘old’ files… I don’t think they’re generated by Windows Defender scanning (system restore is not a folder for temporary files) but who knows…
It could be an infection that is only detected now (with new VPS updates). Better if you can disable your System restore feature, boot, scan with avast! and if you’re clean, enable the System Restore again.