could not connect to Application server

Hi experts,

Kindly help me out, i am exhausted in establishing connection in 3 tier environment.

I am getting an error of connection "could not connect to Appserver" while setting up the 3-tier NAV server setup.
I would like to give a glimpse of all the activity i have done in 3-tier setup so far:
1.) Make two seperate Server, One Appserver and second Dataserver.
2.) Active Directory is in Appserver therefore I have created the domain user in it and grant all access to it by adding it in group of administrator and all possible groups.
3.) Created the domain user in SQL server i.e. in Dataserver and grant ndonavlistner schema to it.
4.) Changed the SQLSERVER service to domain user logon account.
5.) Passed all the commands throught cmd to create SPN account to provide delegation
6.) Enable all the TCP/IP port in SQL Server.

I have followed all the possible steps to build up the connection with Appserver, still i m stuck up somewhere and could not establish connection to the server.
-My firewall is off also on both server.
-I have added the sql port 1433 in delegation of user and firewall port also.
-I am able to login in FINSQL through window login but if run RTC then connectivity error is there.

Could anyone help me where i am getting wrong.


Thanks in advance, looking for a quick reply.

Regards,

Brijen.