I am difficult to understand why the mssql.anggalisdiyanto.net domain is can be accessed and i can login successfully from ASP.NET Enterprise Manager via browser, but not from SQL Server Management Studio. It is error like in below figure :
Help me, thanks in advance.
What is MSSQL instance name you are using?
If you don't specify instance name and connect like "server.com" than default instance name is used "MSSQLSERVER", but instance name of your MSSQL server may be "MSSQLSERVER2012" or "SQLEXPRESS" and in this case you should connect like "server.com\MSSQLSERVER2012" or "server.com\SQLEXPRESS"
You can check instance name in "SQL server configuration manager":
In case instance name is OK, check that remote network connections are "Enabled" for specified IP addresses(but pay attention to security threats):
Security Note
When you allow remote connections to MS SQL server it means that SQL server will be open for password brute force attacks, Denied of Service(DoS) attacks, any kinds of exploit attacks.
All this kinds of attacks may slowdown whole your server.