HHC3004: The HTML tag "tag name" is not a valid HTML tag (it does not begin with a an alphanumeric character).

Problem: All HTML tags must begin with a letter or a number. The compiler encountered an HTML tag that began with some other character. This error may also occur for valid entries that the compiler doesn't recognize. For example, the error might occur for an XHTML file with an XML declaration (e.g., <?xml version="1.0" encoding="UTF-8"?>).

Result: The compiler will ignore the entire tag.

Solution: Typically, you only need to worry about this message if the invalid tag is used to reference another file. To check whether the tag is invalid, look at the HTML code or view the file in Internet Explorer to make sure it displays properly. If the HTML tag is correct, you don't need to do anything other than live with the compiler's warning message.