I was recently unable to reconnect to the US server from Starcraft 2 I found it weird that sometime it works and suddenly for awhole month it doesnt.
So I tried every method, uninstalling SC2 and battle net.
1- Installing Battle Net.
It was stucked on the download and unable to proceed the installation. Tried everything clear cached, dns or whatever.
- Solution, I installed a vpn that connects directly to USA, to my biggest surprised, it finally worked!
2- If you can access battlenet but see that your profile is offline, try to also to use a vpn, especially if you are playing from asia country. It seems to direct you to the TW server, but our account is USA.
3- SC2 unable to connect to US but asia you can, same here, need the VPN
4- Battlenet
Claim that is not region locked, but thats pure BS!