Problem Description

I have a floating network license and get an error message dialog box  containing the phrase:
Licensed number of users already reached
I am quite sure that nobody else on the network is using the license.

The detailed error message displayed by COMSOL:

Could not obtain license for COMSOL Multiphysics GUI.  
License error: -4.  
Licensed number of users already reached.  
Feature:     COMSOLGUI  
License path: C:\Program Files\COMSOL\COMSOL60\Multiphysics\license\license.dat;  
FlexNet Licensing error: -4,132. ""   


If you are a classkit license (CKL) user, please refer to Knowledge Base 1078.

If you are using a NSL or CPU license on Linux, please refer to Knowledge Base 1318.

Make sure that there are license seats available

First of all, make sure that you are really not over-drafting the number of users in the license pool. To check who is currently using the license seats of your license, please see Knowledge Base 1142. When you have ascertained that the number of concurrent users do not exceed the number you have licensed, go on with the troubleshooting guide below.

Linux specific solutions

If you want to run multiple COMSOL sessions simultaneously on a Linux computer, they have to be started from the same terminal window. You can do that by adding an "&" at the end of the "comsol" start command in order to keep the terminal window active after the first session has launched.


comsol & comsol &

from the same terminal will start two COMSOL sessions and only use one license.  If you on the other hand use different terminal windows for each command, each terminal will check out a new license seat.

LiveLink for MATLAB on Linux

If you are licensed the COMSOL LiveLink for MATLAB, and try to start COMSOL with MATLAB, and also start a COMSOL Desktop, use the following command to start the COMSOL with MATLAB process: comsol mphserver matlab -mlroot MATLAB_path -silent &
This will keep the terminal active for you to start a new COMSOL Desktop, from the same terminal window as before.

When running Cluster Jobs

To avoid using multiple license seats when running Cluster Jobs while also running COMSOL with a User interface on your local computer, please make sure of the following:

  • That you have the same username on the cluster and the local computer.

  • That you are using the Batch licenses for the cluster job. For more information about Batch licenses, see Knowledge Base 1142