My current network setup has two servers: a Windows 2008 R2 with TMG 2010 as edge firewall (TMG server), a second 2008 R2 with DC, DNS and Hyper-V roles (DCDNS server). I was trying to install SBS 2011 as a child partition on DCDNS, first I installed SBS 2011 in English and did the migration successfully. However, later on, I found that I can't change the display language in SBS 2011 once it's installed (but the clients require a different language), so I had to re-install the SBS in a different language. It is during the re-installation that the problem came up: the migration can't be completed with some error message stating "can't access the source server". I re-ran the migration preparation tool, but it didn't make any difference. I wonder if it's because the source server can only be "migrated" once.

Since I only need to setup a handful of users and computers, so I decided to do a new install of SBS and picked a different domain name. But I can't get the SBS to connect to LAN: it can't ping other servers, neither can other servers ping the SBS server. I've tried to stop the DC/DNS services on DCDNS and restart SBS, but with no difference. Anyone has idea how to fix this problem?