Symbolic Math Toolbox is installed but does not work

I have been trying to use the 'syms' command for a simple task and the following error arises:

'syms requires Symbolic Math Toolbox'

This happens even though I have the toolbox installed, having followed the settings and path of the default MATLAB installer. The error dissapears whenever I try to install the toolbox again, only for the system to find out that, indeed, it's already installed. But it reappears whenever I close the program and open it again. This has happened in three separate instances and I can't make sense of it.

Why could this be happening? Is it some issue with shared libraries or program files?

[Walter Roberson]

Do you happen to have Maple also installed?

[Simón Rodríguez Franco]

I don't.

I have found a question in the forum with a similar issue, and the user seemed to have Maple installed. Apparently there is a 'syms' function from that source and both functions may overshadow each other. I followed the advice given to them and my problem persists. So I don't think it has to do with interferences between softwares.

[Walter Roberson]

I would suggest using pathtool to explore whether symbolic/symbolic and symbolic/graphics and symbolic/tasks are listed in the directories.

I would suggest testing with

restoredefaultpath; rehash toolboxcache

followed by

savepath

I am speculating that maybe the internal savepath are failing, that perhaps you do not have write access to the path file.

Answer 1

[Shuba Nandini]

Hello Simon,

I understand you are encountering an error while using “syms” function. The error ‘syms requires Symbolic Math Toolbox' usually occurs when the license checkout fails.

To resolve the issue, please follow the below troubleshooting steps:

• Make sure that the Symbolic Math Toolbox is properly installed and licensed. You can verify by running the following command in the MATLAB Command Window:

>>ver -output

This command should list the Symbolic Math Toolbox.

• Verify that your license for the toolbox is active with the following command:

>> license('test', 'Symbolic_Toolbox')

If this command returns 0, there could be an issue with your license.

• Try to reinstall the MATLAB and see if the issue persists.
• Try running the following command in the MATLAB Command Window to diagonize the issue:

>> [status, errmsg] = license('checkout', 'Symbolic Math Toolbox ')

If the error message displays ‘License Manager Error -5’, please refer to the following MATLAB Answers link to know how to resolve license checkout issue:

https://www.mathworks.com/matlabcentral/answers/98719-why-do-i-receive-license-manager-error-5

I hope the above provided workarounds will resolve the issue!