Siemens S7 / PLCSIM Problem

I am using Step 7 v5.4 and CFC v6.1 and I am trying to simulate a program in PLCSIM. From Simatic Manager, I am able to download the hardware, but when I try to download the charts, I get an error 15:8452 - "S7 program (online) not found."

I have my PC/PG Interface set to PC adaptor (MPI).

Any help would be appreciated.

For a quick experiment, try to download from Simatic Manager the blocks folder. I am assuming you compiled the charts and you see the SCL blocks that were created with the compile in CFC.

Is your PLCSIM uptodate like your STEP7 ?
In PLCSIM v5.4, there are separate drivers for simulation, all starting with "PLCSIM". For MPI, the driver should be set to PLCSIM(MPI).
In the past you had to select the "normal" MPI driver. Dont kown if that is possible with v5.4.