I have a couple different machines I work on. Aspire remembers the post processor I'm using between sessions. When I change projects I make sure I confirm the post processor when saving toolpaths. When I'm working with the same project I have gotten out of the habit of confirming the post processor when I save the toolpaths. Ooops!
When I upgraded to 9.5 everything transferred over. Posts, tool database, etc. What didn't transfer was Aspire's memory of the last post processor I was using. I continued working on my current project after the upgrade. I even converted it to the new rotary job type. What I didn't check was that the post processor was correct when I started saving toolpaths. The new version of Aspire just used the first post it found in my post directory. Sadly, this was not the post I needed.
Fortunately I noticed something was amiss when my spindle didn't turn on when I started my job. Less fortunately, I assumed it was something wrong with the machine since I had just completed a rebuild on it. After a lot of head scratching and hardware troubleshooting it finally dawned on me that the gcode didn't look right. That's because it was for a different machine.
Lesson learned. Always confirm the post processor when saving toolpahts.