Problem Details Error: *** Fatal Error: Access Violation at 0X000007FE8A3840FD Module: quartus_fit.exe Stack Trace: 0x1140fc: pl_propagate_constraints + 0xfc (fitter_vpr20kmain) 0x113576: pl_alloc_and_load_constraints + 0xb6 (fitter_vpr20kmain) 0x1017f3: pl_alloc_and_load_placement_optimization_data + 0x43 (fitter_vpr20kmain) 0x30f81b: aa_pl_initialize_vpr_placer + 0xab (fitter_vpr20kmain) 0x30edd1: aa_try_place + 0x71 (fitter_vpr20kmain) 0x26df71: aa_flow_do_placement_attempt + 0x21 (fitter_vpr20kmain) 0x26b5a9: aa_flow_place + 0x149 (fitter_vpr20kmain) 0x26b16d: aa_flow_fit + 0x11d (fitter_vpr20kmain) 0x5735ae: VPR_QI_FACADE::vpr_qi_main + 0x6e (fitter_vpr20kmain) 0x3384e: fitapi_run_vpr + 0x7e (fitter_fitapi) 0x57488: FITCC_EXPERT::run_vpr + 0x138 (FITTER_FITCC) 0x56f55: FITCC_EXPERT::place_and_route + 0xf5 (FITTER_FITCC) 0x5641d: FITCC_EXPERT::invoke_fitter + 0x69d (FITTER_FITCC) 0x23af6: fygr_execute + 0x1a6 (fitter_fygr) 0xe910: fmain_start + 0x900 (FITTER_FMAIN) 0x41b1: qfit_execute_fit + 0x1bd (comp_qfit_legacy_flow) 0x5384: QFIT_FRAMEWORK::execute + 0x2a0 (comp_qfit_legacy_flow) 0x267f: qfit_legacy_flow_run_legacy_fitter_flow + 0x1c7 (comp_qfit_legacy_flow) 0x14410: TclInvokeStringCommand + 0xf0 (tcl86) 0x161e2: TclNRRunCallbacks + 0x62 (tcl86) 0x17a65: TclEvalEx + 0xa65 (tcl86) 0xa6f8b: Tcl_FSEvalFileEx + 0x22b (tcl86) 0xa5646: Tcl_EvalFile + 0x36 (tcl86) 0x12606: qexe_evaluate_tcl_script + 0x376 (comp_qexe) 0x11864: qexe_do_tcl + 0x334 (comp_qexe) 0x16755: qexe_run_tcl_option + 0x585 (comp_qexe) 0x380c3: qcu_run_tcl_option + 0x1003 (comp_qcu) 0x160aa: qexe_run + 0x39a (comp_qexe) 0x16e51: qexe_standard_main + 0xc1 (comp_qexe) 0x2233: qfit2_main + 0x73 (quartus_fit) 0x12e98: msg_main_thread + 0x18 (CCL_MSG) 0x1467e: msg_thread_wrapper + 0x6e (CCL_MSG) 0x16660: mem_thread_wrapper + 0x70 (ccl_mem) 0x12761: msg_exe_main + 0xa1 (CCL_MSG) 0x287e: __tmainCRTStartup + 0x10e (quartus_fit) 0x1556c: BaseThreadInitThunk + 0xc (kernel32) 0x5372c: RtlUserThreadStart + 0x1c (ntdll) End-trace Executable: quartus_fit Comment: I have Two varients setup for this MAX V Device (with watchdog & No Watchdog). When I switch tot he No Watchdog Varient, I'm not able to compile, however, using the With Watchdog varient I am able to compile. Please help! System Information Platform: windows64 OS name: Windows 7 OS version: 6.1 Quartus Prime Information Address bits: 64 Version: 18.1.0 Build: 625 Edition: Standard Edition