I just resolved this issue for myself--also running a new ASUS computer. I had to disable the Reason Core Security app that was running supplemental to McAfee. Once I did that, I was immediately able to load contents from the box into my inventory.
Check your Anti-Virus/Anti-Malware firewall, etc settings, or try disabling them for 10-15 minutes to test. More than likely, that could be your issue, as well.