# About MTCMS Library Custom Windows software installed on a host PC can communicate with MagTek Common Message Structure (MTCMS) devices via USB, network interface, or serial interface using the MTCMS library. The supported platforms for Windows C++ projects include Windows 7, Windows 8/8.1, and Windows 10. The Windows C++ project should contain references to the main library file: MTCMS.dll. --- # Agent Instructions: Querying This Documentation If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question. Perform an HTTP GET request on the current page URL with the `ask` query parameter: ``` GET https://developer.magtek.com/hardware/oem-readers-and-components/oem-readers/odynamo/documentation/programmers-manuals/common-message-structure-mtcms-programmers-reference-manual-c++/about-mtcms-library.md?ask= ``` The question should be specific, self-contained, and written in natural language. The response will contain a direct answer to the question and relevant excerpts and sources from the documentation. Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.