I had the same issue pop up when I try to start the Trailblazer questline for the Ilovemaplesaga chair now the game tell me the firewall is blocking it
Getting this now too. After about 3-5 minutes, idle or active doesnt matter. More info: reinstalled the game, changed compatibility to XP SP2 and still happens, but now the game stutters every few seconds as well. Leaving settings as is, the stuttering and disconnection (not more storage error) happens when I am in full screen mode. Geforce GTX 1080, intel i7 quad core 3.6ghz, 16 GB DDR4 RAM. Being in windowed mode appears to not cause me to disconnect. odd Final edit for a possible solution: I had "geforce experience" application installed and upon uninstalling it I have no problems anymore. Not sure if it was a compatibility issue or I had a corrupt version of that software (it acted very strangely), but removing it fixed a lot. Good luck