Here is the text of the error:
A network-related or instance-specific error occurred while establishing a connection to SQL Server. The server was not found or was not accessible. Verify that the instance name is correct and that SQL Server is configured to allow remote connections. (provider: TCP Provider, error: 0 - The wait operation timed out.) (Microsoft SQL Server, Error: 258)
I initially tried with the default security group that was created with the instance, but when that didn't work I created a new security group and modified the instance to use it.
I tried this connection setup to connect: Server Type: Database Engine Server Name: valuationdlsdev.ck1qvjqhglyg.us-west-2.rds.amazonaws.com,1433 Authentication: SQL Server Authentication Login: the Master User Login I created when creating the RDS Instance Password: the Master User Password I created when creating the RDS Instance
At this point I'm wondering if port 1433 is not open, because I feel like I've tried everything. Could someone please help me.
In case anyone comes across this post looking for an answer, I just wanted to updated and make sure it's there if anyone needs it. The issue here turned out to be that I misunderstood the way "Publicly Accessible" works and set it to "Yes". Apparently it should have been set to "No". "Yes", however does work for the SQL Server Express version.