Hi First of all, sorry if this topic has been covered but I have found the answer I have create a simple circuit to increase a little signal using an operational amplifier, just to learn how to simulate and create pcb with easyeda I have used basic componentes being in "sim mode" and the simulation was nice. But I need to include a DC Power Jack and a pin header just to expose negative input. So I switched to STD mode and found them (because there are no avaible in SIM mode). Those components are very simple so I thought they dont need a model. Then I create the PCB design correctly. But when I switched to SIM mode again to run a new simulation this error showed up. "There are some parts haven't spice model, please use EELib".....or you can assign the spice model for them: J1: HDR-M-2.54_1x1. So can use those simple components in a simulation? Or can I just disable them for the simulation? Or do they need a model? (A model for a header pin????) I am very frustrated because I dont what to clone the scheme, one for simulation and other to update the PCB Please help [https://oshwlab.com/herrero.daniel/new-project_copy](https://oshwlab.com/herrero.daniel/new-project_copy) [https://easyeda\.com/editor\#cmd=new\_schematic\,cmd\_for\_project=f4109338083d46dab785c2c669e386fa](https://easyeda.com/editor#cmd=new_schematic,cmd_for_project=f4109338083d46dab785c2c669e386fa)<br> <br>