Misfit-RX Then I don't know what else to tell you, sorry. I already listed all the potential causes I and the person I talked to could come up with. I suppose you could wipe the computer entirely, but that would be a lot of work without guaranteeing a fix.
Just to make sure though, did you take the laptop somewhere with a different network and try to repair the game there? I reread your newer responses and don't see any mention of that.
And please also check whether your CPU is overclocked. If it is, revert to stock settings. It would be very strange for an unstable overclock to cause this issue, but the processor affects everything, and problems with the processor can get very weird.