The full, complete solution is:
wkhtmltopdf.exe --enable-local-file-access "E:\INPUT-FILE.html" "E:\output-file.pdf"
CRITICAL: It's important to put it in this order. Even though --enable-local-file-access is a named parameter, which means it can be identified anywhere in a command, the order is necessary.
Consider the currently-accepted answer: Merely "add on" the parameter. That simply doesn't work. And you'll get this result if you attempt using it:
Loading pages (1/6)Warning: Blocked access to file E:/gutenberg/metro_files/illusc.jpgError: Failed to load about:blank, with network status code 301 and http status code 0 - Protocol "about" is unknown