% MATHSTAT_166: Dynamically loadable module is unavailable on this platform: IMSL.

In the latest releases of IDL, users who run Advanced Math and Stats (IMSL) on Windows or Mac machines that are 64 bit may encounter the following error :

% MATHSTAT_166: Dynamically loadable module is unavailable on this platform: IMSL.

When this error occurs, it means that IMSL is not supported in the 64 bit version of IDL. It is however supported in the 32 bit version of IDL and all of our 64 bit installs allow you to launch the 32 version of IDL. Please keep in mind, you will only need to launch IDL in 32 bit mode when you want to work with IMSL. For all other processing not using IMSL, you can continue to run in 64 bit mode of IDL.

On Windows Machines, to launch IDL in 32 bit mode,
Click on Start > All Programs > IDL 8.1 (or 8.0) Folder > Tools Folder > IDL (32-bit)

On Macs, you may launch IDL in 32 bit mode in two different ways. The first way is if you are launching IDL from the terminal window.

To launch IDL command line in 32 bit mode from the terminal window, issue the command: idl -32
To launch the IDL workbench in 32 bit mode from the terminal, issue the command: idlde -32

The second way is to launch IDL from the applescript:
Open a Finder window > select Applications > ITT > IDL > IDL 8.1 (or 8.0) > IDL32