Quote - I get the same error on a new PC I'm building with Windows 7 64-bit, again running Poser 8 SR3. I note that both machines have "(x86)" in their path, and wonder if that is the problem.

No that's nothing to do with it, because that's the path on BB's machine (this is just the way Python reports the source location for compiled files).

If you're actually installing under "Program Files" make sure that the files really are where you think they are.