MLC (Microsoft Language Interface Pack)

The MLC System file format

If a computer runs on the Windows operating system, it comes with a pre-installed language interface pack (LIP). The LIP uses MLC files. These files contain translation information that is stored as binary data. Thus, the MLC files help the operating system to display the user interface of Windows in different languages to the user. It is not advised to open these files manually. They are automatically used by the Windows operating system. Manual changes of the content can cause issues to arise in the implementation of the MLC files using LIP.

Technical details of MLC files

The restriction when it comes to the Windows language interface pack are linked to a) the operating system version and b) the already installed languages. MLC files and LIP installations of Windows Vista, for example, can not be used on Windows 7. Furthermore, language packs like Basque need a “parent language” to be installed in order to be installed themselves. In the case of Basque, it has to be either Spanish or French. When using Package Installer to install a new LIP or when copying the LIP to another Windows machine, keep in mind that you need to rename the MLC files and thus change their file extension. Instead of MLC, these cases require the CAB file extension.

More information about the MLC file format

File extension .mlc
File category System
Associated programs Windows Operating System
Developer Microsoft