Error message using functional connectivity

 Hello, 
I'm trying to run functional connectivity on a MacBook and I received the following error message when trying to perform. The error message is 

Error using ==> rest_WriteNiftiImage at 92
Meet error while writing the data

This is what shows up in MATLAB
Exception occured.    ()
    Error using ==> rest_WriteNiftiImage at 92
Meet error while writing the data
    92#line,        rest_WriteNiftiImage,    in "/Applications/MATLAB/REST2007V1.3_090525/rest_WriteNiftiImage.m"
    79#line,        rest_writefile,    in "/Applications/MATLAB/REST2007V1.3_090525/rest_writefile.m"
    112#line,        rest_SphereROI,    in "/Applications/MATLAB/REST2007V1.3_090525/rest_SphereROI.m"
    126#line,        fc,    in "/Applications/MATLAB/REST2007V1.3_090525/fc.m"
    1323#line,        btnComputeFC_Callback,    in "/Applications/MATLAB/REST2007V1.3_090525/fc_gui.m"
    96#line,        gui_mainfcn,    in "/Applications/MATLAB/MATLAB_R2009a.app/toolbox/matlab/guide/gui_mainfcn.m"
    35#line,        fc_gui,    in "/Applications/MATLAB/REST2007V1.3_090525/fc_gui.m"

I use Mac OS X Version 10.5.7
Hardware Overview:

 Model Name:    MacBook
  Model Identifier:    MacBook2,1
  Processor Name:    Intel Core 2 Duo
  Processor Speed:    2.16 GHz
  Number Of Processors:    1
  Total Number Of Cores:    2
  L2 Cache:    4 MB
  Memory:    2 GB
  Bus Speed:    667 MHz
  Sudden Motion Sensor:
  State:    Enabled