Still it says "command failed" as you can see below.

 

C:\Han\slide>mpost --tex=latex 2MS2
This is MetaPost, Version 0.993 (Web2C 7.5.6)
(2MS2.mp [0] [1] [2] [3] [4] [5] [6] [7] [8] [9] [10]makempx: Command failed: mp
to -tex 2MS2.mp

>> 2MS2.mp
>> 2MS2.mpx
! Unable to make mpx file.
l.151 label.lft(btex
                     $A$ etex, z8);
11 output files written: 2MS2.0 .. 2MS2.10
Transcript written on 2MS2.log.

 

C:\Han\slide>makempx -tex=latex 2MS2.mp 2MS2.mpx
makempx: Command failed: mpto -tex 2MS2.mp

Thanks,

Steve