when I try to do a simulation in Modelsim with Nios2.... starting from Run as -> Nios 2 ModelSim I see this messages in ModelSim Transcript Window: # vsim -gui DE4_SOPC_sim.mpf # ** Error: (vsim-19) Failed to access library 'DE4_SOPC_sim' at "DE4_SOPC_sim". # No such file or directory. (errno = ENOENT) # Error loading design do you know what error is ???