Whoa Elroy. That is one fast response.

Yep, your code works. Your ShellExecute looks slightly different from mine (I don't use StrPtr for example - which shouldn't make any difference but who knows) so I tried your version.
And then it doesn't seem to work when the .htm file is located on your hard drive. Can you confirm this? Internet access cannot be guaranteed for my users so we have to install the htm file on a local or perhaps network drive for them.