My PC is running Windows 10 x64 which has a virtual machine that is a Windows 7 x86. This virtual machine has a SQL Server instance SQLEXPRESS. This server is provisional, in the future we are going to use another computer, this is for testing purposes.
I have developed a Windows desktop app which connects to this server to read and write.
Here is the connection string:
<add name="Importacion" 
     connectionString="Data Source=WIN-EIUKNBIVIED\SQLEXPRESS;Initial Catalog=Importacion;User Id=administrador;Password=contraseña" 
     providerName="System.Data.SqlClient" />
This has been developed in C# in Visual Studio. I have created an installer with all the dependencies. It works in the virtual machine.
Problem
When I install it on another computer, I get a SQL Server error #28.
Hints
- Ping in virtual machine works to SQLEXPRESS
- Ping from native PC to virtual machine works
- Ping from native PC to SQLEXPRESSdoesn't work
Things that I already tried
- Enabling TCP/IP ports
- Setting to connection to the server as mixed (Windows and SQL Server)
- Disabling firewall on both computers
- The new user that use the connection string have permission to do everything
- The remote connection is enabled
 
    