If you ever have problems opening CHM files over a network connection or from the Internet, you will probably get a message to the effect of

"Action canceled Internet Explorer was unable to link to the Web page you requested. The page might be temporarily unavailable",
"The page cannot be displayed"

here are the most likely causes and solutions:

• The file name or path contains the # symbol: Rename the file or open it from a directory without a # in the path.

• Its a HTMLHelp Zone restriction: Download the registry fix, right click and choose "Merge"