andy-roo my situation is almost the same as yours, but in my case, I can log in only at work, thus using the same laptop at work and home.

The only reason I currently can think of is different Internet Service Providers. Some may be blocking ports and others not, but then again, I work for a big corporate and only port 80 (Inet traffic) is open here as they are very strict on security. At home I manage my own firewalls thru Mikrotik Routers and sure as hell do not blok/drop ports needed for normal inet traffic.

Thus leading me to think it can be ISP related.