I'm trying to set up MSSQL 2012 for a school project and I need to be able to connect to it remotely as my teammates will also be working on it.

I did a clean install of SQL Server 2012 Express.

Knowing I can't connect remotely straight off, I tweaked the settings that needed tweaking according to the internet.

What I did
1.Made sure remote connections were allowed
2.Enabled TCP/IP
3.Removed 0s from Dynamic ports and set 1433 in TCP Port
4.Enabled Named Pipes
5.Created Outbound and Inbound traffic rules in the firewall for TCP port 1433 and UDP port 1434
6.Port forwarded 1433 to my "server" and 1434 too
7.made sure I was pingable
8.SQL Server authentication is enabled
9.I have restarted my computer so that changes to the config are saved

So whenever I try to connect using management studio on another computer than the server using myusername.dyndns.org\SQLEXPRESS I get error 26

I have been searching for different solutions for 3 hours with no luck.