BUG: Tabs in .H File Cause Compiler Error HHC4014 in HTML Help

When you compile an HTML Help project, you may receive the following HTML Help compiler warning:

This is caused by characters in the include (.h) file that are not recognized by the compiler, such as tab characters.

Edit the include file so that there is exactly one space between each #define statement and what it is defining. Do not use tab characters.

Microsoft has confirmed that this is a bug in the Microsoft products that are listed at the beginning of this article.

When you create an HTML Help project with context IDs, it is possible to put the context ID's in a separate include (.h) file and include the file by specifying it in the [MAP] section of the project. In this file, there must be exactly one space between the #define statement and the defined constant, and you cannot use tabs. You can use tabs elsewhere in the file.