Error during the setup of sharepoint. Can not connect to database master at SQL server at {ServerName}. The database might not exist, or the current user does not have permission to connect to it.

personal
 
I have a server database that we call SRV-DB in a machine 16 gb which is one Sql Server 2008 to host the project server and sharepoint.
 
I have a web server + app server (SRV-APP) which will install a sharepoint + PS2010.
 
When trying to run the SharePoint Products Configuration Wizard gives me the error below:
 
Can not connect to database master at SQL server at {ServerName}. The database might not exist, or the current user does not have permission to connect to it.
 
- I have disabled the firewall server BD (BD-SRV)
  - The TCP / IP of my machine BD is Enabled.
  - Have reinstalled twice sharepoint
  - When you give a ping from my machine it recognizes the app server BD