Named Pipes Provider, error 40 - Sql Exception (0x80131904)

[simkar]

Error:
provider: Named Pipes Provider, error: 40 - Could not open a connection to SQL Server

SqlException (0x80131904)

General Info:
Application is on server1(outside the firewall)
Database is on server2(inside the firewall) SQL Server 2005
Login is server authentication (Windows and Server Authentication is checked)
Remote server is allowed.
TCP/IP and Named Pipes is checked
Login and password has been created in the server security.
Read and write permission are set up.
Login and password has been created for the database.
Select, Update, etc. has been granted for the database user.
Network has both way communications open.

Must the application server1 have SQL server installed (it is not installed) to be able to communicate with the SQL Server database, server2?

Solution very welcome, Thanks.

[simkar]

For anyone who has tried all the troubleshooting helps without success.
This was my issue.
Changed the data source from a named server to the IP address and got through the firewall.

[sbsxrx]

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