Thanks for your reply.
I upgraded to 4.7.1 and recompiled a book which worked OK previously, and when I tried to run the .exe file I got the message that HE Server could not find any files with an .html extension.
I uninstalled HTML Executable 4.7.1 using Revo uninstaller and downloaded a new copy and reinstalled it.
Recompiled the book, when I ran the .exe file again I got the Web Browser message “Unable to download introduction.html from heserver. Unable to open this Internet site. The requested site is either unavailable or cannot be found. Please try again later.” The same message for any other files in the book with .html extensions.
In the opened book, the message “Navigation to the webpage was cancelled.” All the other .htm pages opened. I renamed introduction.html to introduction.htm and recompiled the book and everything worked OK.
I uninstalled 4.7.1 again using Revo uninstaller and reloaded HTML Executable version 1.2.1.0. I renamed all the necessary files back to .html and recompiled the book. This version successfully compiled and the executable ran OK recognising all the .html files.
DATA:
Running Windows Vista Business Service Pack 2 with all updates in place.
Windows Internet Explorer9 version 9.0.8112.16421IC Update Versions: 9.0.34 (KB3008923)