I was going to say it, but here's a post by a "Microsoft Moderator" not sure what that is. HOw can I install Homegroups in Windows 7 when ipv6 is already enabled oh..ok, I'll say it anyway because she says "Temporarily disable", I've got to say uninstall them completely...you can always put them back later. There is also some information in there and a link to another page which talks about editing the registry. Do so at your own risk and back it up first. Just try uninstalling zonealarm and any other internet security suites that may be causing a problem including antivirus programs. Hope this will help...post back and let us know
You say "I did the following" but you don't say what the "following" is? But it seems you were able to create a homegroup, after doing something. Maybe you could tell us something about your "other computer" (OS, 32 or 64bit, how it's connected to the network, etc.). Just some information to help us help you.