This page is linked from the build system. Do not remove it without making sure it links to useful information for building Firefox 3
atlbase.h is a header file which is provided by the Microsoft Active Template Library.
The error "System header atlbase.h is not available" indicates that you do not have a copy of ATL in your INCLUDE directory. There are several ways you can solve this problem:
Use the Professional Version of Microsoft Visual C++
The professional version of Microsoft Visual C++ comes with ATL headers.
Use the Windows 2003 SDK
The Windows 2003 SDK is a free download and is the last version of the Windows SDK to come with ATL headers.
NOTE: The Windows 2008 SDK, which the 2003 SDK page points you to, doesn't have the ATL headers.
You should restart start-msvcX.bat after installing the Windows 2003 SDK.
Disable code that uses ATL
ATL is used by only a small portion of our codebase. You should be able to disable these features and do a build without ATL: