Scanning comparison: scanning all files vs. scanning default + additional file types

The on-access scanner treats scans differently depending on whether it is configured to scan all files or to scan default plus additional file types.

When scanning All files, the scanner scans every file type for all possible threats.

When scanning Default + additional file types, the scanner examines a specific list of files based on the file types you select.

Default file types: the scanner examines the specified file type only for threats that attack that file type. For example, when scanning an XLS file, the scanner scans XLS files for threats that attack XLS files, such as macros. The scanner does not scan the XLS files for threats like PE (portable executable) infectors or even the EICAR test file. If the XLS file is renamed to that different file type, the scanner scans the renamed file for the threats that affect the newly named file type.
Additional file types: the scanner scans the file type for all possible threats, as it does for All files.