“Scan via context menu” generally refers to the ability to right-click on a file, folder, or drive in your computer’s file explorer to initiate a malware scan specifically on that item. This provides a quick, targeted alternative to running a full system scan.
Antivirus Integration: Major antivirus software (e.g., Windows Defender, Kaspersky, Bitdefender) automatically adds a “Scan with…” option to the Windows context menu upon installation.
Targeted Scanning: When you select this option, the antivirus software scans the selected item, including any sub-files contained within it, for threats.
Malware Analysis: According to forums, when scanning a specific file (like an archive or executable), the tool may show that it is inspecting smaller, nested files within that item to ensure nothing malicious is hidden.
Convenience: It is designed for checking specific downloads, external drives, or suspicious files without needing to open the main antivirus application.
Windows Defender: You can specifically use Regedit to add “Scan with Windows Defender” to the context menu if it is not already present, which allows for a direct right-click scan. How to use the Scan Context Menu
Right-click on the file, folder, or drive you wish to scan in Windows File Explorer.
Look for your security software’s icon or name (e.g., “Scan with Windows Defender” or “Scan with Kaspersky”). Click the option to start the scan.
Note: For scanning physical paper documents via a computer, you would use a specialized scanning app, not the context menu, as shown in this guide on Windows scanning. Scan via context menu problem – Kaspersky Internet Security