In order to create external string resource DLLs, you need to have the appropriate Resource Compiler and Linker for the system.

When applications are developed for ESL for Windows, you need to obtain Windows versions of the Resource Compiler and Link programs. The ESL external string support has been developed so it is very simple to use with the tools provided with Microsoft Visual Studio, but any development tools that support Windows resource files and can create resource DLLs should be usable.