How do I remove old installations in broken down computers?

I have had a single-user Matlab license since 1989 (Matlab author since 2009) and, over the years, I have installed Matlab on many of my personal laptops, several of which are now obsolete and un-operational. The last time I bought a new laptop I had trouble down-loading Matlab because apparently there is a limit on how many computers and individual user can have Matlab on.

I am about to buy a new computer. Can someone tell me (1) how I can find out how many of my old computers have Matlab installed on them and (2) how I can remove the installations on the non-operational computers? Thank you.

Answer 1

[Image Analyst]

You can login to your account on Mathworks.com and see all your licenses. You can then pick one or more to deactivate.

Any that are not listed there may be installed on some computer but have been deactivated and, as far as Mathworks licensing cares, they don't exist. If you have those, or any computer, you can use control panel to uninstall any installed version of MATLAB, regardless if they are a current activation or not. You can go into Program File\MATLAB and delete any folders or files not uninstalled by the installation process. When you uninstall an activated installation, it will ask you (at the end) if you want to deactivate it.

[David Koenig]

Thank you for your response. I logged in, as suggested, on my two operational laptops, my iPhone and my tablet and on each I found my license but it does not say what computer it is for (or how many computers the license is active on).

Am I looking at the wrong place? Thanks again for your help.

[Image Analyst]

Not sure where you found the license - on the local computer or on the Mathworks web site. If you just want to deactivate everything and then activate the one single computer that you plan on using, you can do that (deactivate any and all activations) from any computer -- just login to your account with the web browser on any computer. It can even be a computer at the library - it doesn't matter. Just login and deactivate all licenses that appear. Then just start the computer you want to use and activate it on only that one.

[Walter Roberson]

When you log into your account in MATLAB Central then in Installation and Activation, you will see a list of license numbers. Click on one of them and you will be shown a list of activation labels.

Activation labels can have their label customized, but the default for them is the identifier of the hardware. For Windows that might potentially be the hard drive serial number; if not, or always for MacOS and Linux, it would be the hostid of the lowest hardware interface Media Access Control (MAC). In either case click on the item to see the hardware id. If you did not happen to customize the label you would need to check your records to find out which device has that hostid.

Answer 2

[Walter Roberson]

You might need to use the steps in https://www.mathworks.com/matlabcentral/answers/99859-how-can-i-deactivate-matlab-on-a-machine-i-cannot-access?s_tid=srchtitle

There is no limit on the number of different computers you can have MATLAB overall installed on. There is a limit on the number of different computers any one license can be activated on.

There is also a limit on the number of different computers on the number of computers that that a license can be installed on with or without activatation, but that license provision is pretty meaningless as long as you do not go around advertising that you are planning to deliberately run the installer without activating the product. It means that in theory a student needs to deactivate MATLAB on their existing system before starting to install on a new system they are planning to move to, but in practice with modern installers in interactive mode, you can download and start the installer but might get caught needing to go back and deactivate before the installer will run (because the modern installer checks activations first)