I setup up an SQLExpress instance on a dedicated server. I configured
the surface area to allow TCP remote connection. But I just can't
connection from my laptop over the internet.

I use IP address + INSTANCE as server name (like
123.123.123.123\SQLEXPRESS)
and use sa account

always get the error:26-Error locating server/Instance Specified.

How can I access from remote
1) via Management STUDIO
2) via .NET (what is the connection string)

THANKS

JOhn

Some detailed info:
In surface area configuration, I enabled
Remote Connections (both Named Pipe and TCP), and
SQL Server Browser
Disabled all the firewall just for simplicity.

But still no luck and got the same error again and again.