Hi!
You have to see if you are getting the .dx file. The default of the
program is to put it at the same directory where it was installed, along
with the other temporary files: .in, .pqr and .pdb. In case of not, I
got the same problem and the solution was: the PDB that you load can`t
have chain ID, the aminoacids can`t have alternate conformations and the
program only accepts the standard residues. If everything is all right
with your PBD, after run the APBS you gotta have the .dx at this
directory. Once you got the .dx (the pymol will show the apbs.map) click
at the update (on Visualization) and then show.
Hope this help!
sandra