Unknown characters folder virus infection

This infection was why I installed Norton antivirus knowing it to be the best protection. Many of my folders got infected I do not know how. I was using Kaspersky Anti Virus. The folders have become unreadable. After i installed Norton security, I scanned the infected folders but it did not identify any threats. I found the same issue online where they have posted a screenshot. Anyone with ideas on how i can rectify this infection, kindly inform me. Thank you.