why minGW could not be downloaded from add on menu of matlab R2017a?it is failing to download again and again??

now the issue is '>> mex -setup Error using mex No supported compiler or SDK was found. You can install the freely available MinGW-w64 C/C++ compiler; see Install MinGW-w64 Compiler. For more options, visit http://www.mathworks.com/support/compilers/R2017a/. but when i am trying to download the concerned version of minGW from the add-on menu.it fails all the time..HELP '