AKABAK Version 3.1.7 b99 (Demo Version)

I realize this is very late response but no one answered and you probably already solved it.

Its a quirk. Select the "VACS" icon in the toolbar to launch and connect to VACs, then run your freq response script. This can happen when you close VACs then try to re-run an observation script.

BTW this question would have gotten a fast response if it were in the Software Tools sub forum. Maybe a moderator could move it.