Environment > Distributing IDL Applications > Creating a Runtime Distribution > Distributing IDL Applications on Removable Media

# Distributing Runtime Applications on Removable Media

The runtime distribution you create using MAKE_RT can be distributed on removable media such as a CD-ROM, DVD-ROM, or flash drive. The application will, in most cases, run directly from the removable media without any need to install files on the end-user’s system. (See Installation Issues: Windows for additional details.)

To distribute the runtime distribution on removable media, simply copy the entire directory hierarchy created by the MAKE_RT routine to the removable media. Users can then execute your launch scripts directly from the media.

For better performance, you may want to instruct your end-users to copy the runtime distribution to a local hard drive. Again, simply copying the entire directory hierarchy from the removable media to the hard drive is sufficient. Similarly, if you distribute the runtime application without physical media (using a downloadable archive file, for example), simply unpacking the archive file on a local hard drive should suffice to install your application.

Note: Copying a runtime distribution onto the user’s hard disk does not “install” IDL in the usual sense. No file associations or symbolic links are created.

## Installation Issues: Windows

When you install IDL for Windows, the installation program ensures that all Microsoft Windows system libraries required by IDL are installed. If you are distributing a runtime application that will run on a Windows system that does not have an installed version of IDL, it is possible (although somewhat unlikely) that the required system libraries will not be present on your end-user’s computer.

If your application does not run correctly on your user’s machine, the missing system libraries may be the problem. The `IDL_DIR``/bin/make_rt` directory includes two small installation programs that ensure the required system libraries are present. You are free to distribute these to your own users. Instruct your users to run the appropriate system library installer if they have problems:

- For 32-bit Windows systems, run `systemdll32_setup.exe`
- For 64-bit Windows systems, run `systemdll64_setup.exe`

Note: The system library installers will only install the required libraries if the correct versions (or later versions) are not already present. These installers will not overwrite later versions of the libraries.