Any executable should be scanned. Control Panel Extension. Similar to a device driver which is executable code and, as such, can be infected and should be scanned. Can be used for a variety of tasks associated with a program. DLLs typically add functions to programs.
Word documents can contain macros that are powerful enough to be used for viruses and worms.
Word templates can contain macros that are powerful enough to be used for viruses and worms. A device driver is executable code and, as such, can be infected and should be scanned. Any executable file can be infected in a variety of ways. Believe it or not, a font file can have executable code in it and therefore can be infected. Help files can contain macros.