Interfacing of Modelsim and MATLAB

I am trying to interface MATLAB 2012b 32 bit with Modelsim PE student edition 10.4a.

When I am writing vsim in MATLAB command window it is showing following error.

Error using hdlsim/l_GetModelSimLibInfo (line 527)

Could not find ModelSim executable vsim. Make sure that ModelSim is installed on this

machine and its executables are on the system path.

Error in hdlsim (line 123)

libInfo = l_GetModelSimLibInfo;

Error in vsim (line 106)

hdlsim(pvpairs{:});

My Modelsim is working properly when I am using it with different code only the interfacing is not working.I have also added Modelsim in my system path. Please tell me what to do with this.

Thanks and regards.