Avast Failure To Clean

Every day, at the start-up of my browser, Avast finds and notifies me of the “malware” shown in the image, below. I have run several scans and Avast is unable to cleanse this. Can you advise as to why Avast cannot address the problem?

https://s10.postimg.org/q9eu073pl/Alert.png

Every day, at the start-up of my browser, Avast finds and notifies me of the "malware" shown in the image, below.
No malware ... URL:Mal = Blacklisted URL or IP

You may try empty your browser cache / history

If you need help from a expert, follow instructions here https://forum.avast.com/index.php?topic=194892.0