What IP addresses are Microsoft using?

I checked my router's log and saw a number of messages saying TCP connection
requests from 65.55.5.NN were blocked, where NN is 78 or 80. The requests
were all meant to go to the four ports FolderShare uses (80, 443, 6571, and
8000). I did an IP lookup and found that 65.55.5.NN is Microsoft, so I'm
pretty sure this must be FolderShare traffic. Since FolderShare seems to be
working OK, I wonder what these attempts are for. If I go into Settings and
check Port Status (in FS) I can see that "Accept Connections" says "Blocked"
on all four ports. So I guess I'm wondering if I should port forward this IP
address to those ports. But the last two digits of the IP addresses changes
occasionally, so I would need a range of addresses to forward. Does anybody
know if I should be forwarding TCP requests to these four ports, and if so,
what IP address range should I use?