MEM error compute source

Hi everyone, I was computing MEM source reconstruction but I continue to receive the following error:
rror: [process_inverse_mem] Sources > Compute sources: BEst
** Line 64: Undefined function 'fminunc' for input arguments of type 'function_handle'.
**
** Call stack:
** >be_minimize_free_energy.m at 64
** >be_solve_mem.m at 56
** >be_launch_mem.m>MEM_mainLoop at 170
** >be_launch_mem.m at 92
** >be_cmem_solver.m at 180
** >be_main_call.m at 148
** >be_main.m at 60
** >process_inverse.m>Compute at 683
** >process_inverse.m at 24
** >process_inverse_mem.m>Run at 149
** >process_inverse_mem.m at 24
** >bst_process.m>Run at 229
** >bst_process.m at 36
** >panel_process1.m>RunProcess at 151
** >panel_process1.m at 26
** >gui_brainstorm.m>CreateWindow/ProcessRun_Callback at 772
** >bst_call.m at 28
** >gui_brainstorm.m>@(h,ev)bst_call(@ProcessRun_Callback) at 296
**
**
** File: A.C./A_C_continous_notch_band/data_1_average_200523_1204.mat
**

I was computing cMEM. My epoch goes from -1500 to 500 ms. My baseline definition has been setted within data [-1500 -500]. Time window [-500 500]. I used all the default parameters of the tutorial.
Do you have suggestions?
Thanks

Hi @gianmarcoduma

It's because fminunc is part of the optimization toolbox of Matlab. The tutorial suggest, if you don' have access to the solver, to change, in the expert parameter section, to change the solver from fminunc to minFunc