Problems running a classkit license (CKL)

Solution Number: 1078
Title: Problems running a classkit license (CKL)
Platform: All Platforms
Versions: All versions
Categories: Installation
Keywords: license error -5 license error -18

Problem Description

I just received the new installation package and installed COMSOL including the new license manager files for my Class Kit option License file (CKL). When I start COMSOL I get one of these error messages:

Could not obtain license for COMSOL Multiphysics GUI.
License error: -18.
License server system does not support this product.
License server system does not support this feature.


Could not obtain license for COMSOL Multiphysics GUI.
License error: -5.
No such product exists.
No such feature exists.


Start the COMSOL application with the classkit option

A reason for the error message can be that you started the COMSOL application without the classkit option enabled. The default installation of COMSOL should lead you right from the beginning, but the desktop icons may have been altered by some user after installation. Here is how you manually start COMSOL in classkit mode:


To use the classkit license, start COMSOL with the shortcut named (Classkit License) COMSOL Multiphysics:

Sometimes it is necessary to create the COMSOL shortcuts manually, for example when COMSOL is installed on a shared network drive. In these cases, add the options below to the shortcut's Target comsol.exe. The complete target should look something like this for 64-bit Windows:

"C:\Program Files\COMSOL\COMSOL54\Multiphysics\bin\win64\comsol.exe" -ckl

Here, C:\Program Files\COMSOL\COMSOL54\Multiphysics represents your COMSOL installation directory.


Start COMSOL with the -ckl option in the terminal window:

comsol -ckl


Access the terminal command the following way:

  • Launch the Terminal application. You find it in the folder Applications/Utilities.

  • In the Terminal window go to COMSOL's bin folder by typing the command:

    cd /Applications/COMSOL54/Multiphysics/bin

  • Then launch COMSOL by typing the command:

    ./comsol -ckl

You can also edit the COMSOL application directly:

  • Open:


    in a text editor. You may need to be an administrator to do this.

  • On the last line, add -ckl at the end. The line should now look like this:

    exec "${here}/bin/comsol" -ckl

See Also

Knowledge Base 903
Knowledge Base 1022


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