.VMX File Extension

A VMX file is a configuration file used by VMware virtualization software such as VMware Workstation and VMware Fusion. It stores settings for a virtual machine created using VMWare's New Virtual Machine Wizard. Each VMX file includes a virtual machine's memory, hard disk, and processor limit settings.

VMX files are paired with and used to load the virtual disk saved in a .VMDK file. They are saved in a plain text format and contain a list of settings in the form of property = value. For example, the setting for a VM's memory limit may be memsize = "512", which means that 512MB of RAM is the maximum memory allowed for that VM.

VMX files saved for VMware Fusion are generally stored within a .VMWAREVM package.

NOTE: If your created a virtual machine an earlier Linux version of VMware Workstation, that machine's configuration file may use the .CFG extension.

For the most part, VMX files are not meant to be opened. However, if you need to manually edit a virtual machine's settings, you can open and edit that machine's VMX file in any text editor. For more detailed instructions, refer to VMWare's official documentation.

Map backup file created by Source SDK, an SDK used to modify games provided by Valve's Steam gaming service; contains a backup of a .VMF map file created by the Hammer Editor component of the Source SDK.

Hammer Editor automatically create a VMX file when a VMF map file is saved. Therefore, they can be used to revert a map back to the last save point.

Configuration file used by Steinberg music production software programs, such as Cubase and V-STack; contains channel and effects settings for an audio mixer; used to save and load custom mixer configurations.