ESET antivirus displays scan options when you insert a removable media device into your computer, and you will be prompted to take any actions. It is a good antivirus, but not perfect. Sometimes the antivirus may stop working, or the scan may take too long. Many factors can cause scan failure. And because of it, the viruses and malware on your device can go undetected. Read the below content to learn about the possible causes and the ways to fix them.