SCP-012.tma

so i dont know how to run this portmapper thing and as well as that tekkit wont launch anymore. i guess its just not meant to be

i just built this new computer and i was excited to finally be able to launch a server so that me and my friends could use some extreme packs without my server dying. Before this i had not the best computer but and it could barely run tekkit classic at more than 20 FPS. but on that last computer i could run servers for all tekkit packs and even non-minecraft stuff like gmod and tf2. for some reason even though im using the same router, and i checked that it was all port forwarded correctly, it doesnt want to work in the slightest. i havent tried gmod and others yet but has anyone else had this problem? i dont want to go back to the other computer just for running servers but i might have to do just that.