License Management (MATLAB Installation Guide for Windows) MATLAB Installation Guide for Windows     Running Multiple Versions of MATLAB If you want to continue running a previously installed version of MATLAB after you install MATLAB 6.5, note the following: The previously installed version of MATLAB must be 5.2.x or higher. Both versions of MATLAB must use the latest version of the license manager (FLEXlm). MATLAB 6.5 requires FLEXlm 8.0d. Replace the processed License File that your previous MATLAB installation uses with the processed License File created during the installation of MATLAB 6.5. To set up this configuration, follow these instructions: Shut down your previously installed version of MATLAB. Stop the license manager. (See Starting and Stopping the License Manager.) Remove the license manager service. (See Installing the License Manager as a Service.) Install MATLAB 6.5 on your client systems. (See Installing MATLAB on a Client System.) Replace the License File used by your existing MATLAB installation with the License File created by the installer during the new installation. This table lists the location of the License File on client systems for different MATLAB releases. MATLAB Version Location of License File on Client Systems MATLAB 6.x $MATLAB\bin\win32\license.dat MATLAB 5.2.x or 5.3.x $MATLAB\bin\license.dat If your existing installation is MATLAB 6.x, replace the license.dat file in the $MATLAB\bin\win32 directory with the file from the same directory in your new installation. If your existing installation is MATLAB 5.2.x, replace the license.dat file in the $MATLAB\bin directory.   Installing the License Manager as a Service Running MATLAB with Other FLEXlm Applications