As tuba said, Accpac runs under Wine, there are problems reported with running FR on Linux, it kinda does not work. Users have reported better success with Financial Link or something like that, I cannot remember exactly what. Linux is not worth the effort IMHO.
If you are running Terminal Server then the question is not relevant, since TS is Windows. In a TS environment Accpac runs on the TS box and therefore it is running under Windows, and FR works just fine. Excel needs to be installed on the TS box.