Client Network Utility cannot create alias for VPN SQL server connection?

I am trying to connect two SQL servers in different non-trusted domains.
SQLServer11 in Domain A and SQLServer22 in domain B. This is through a VPN
connection. Domain A has the VPN server. On SQLServer22 I could ping
SQLServer11.mydomain.local at IP address 192.168.100.50. On SQLServer22 I
use the client network utility to create an alias for SQLServer11 as
follows:
Network Libraries: TCP/IP
Server name: 192.168.100.50
Port No: 1433
Server alias: SQLServer11
Then I registered the new SQLServer11 in enterprise manager. But I keep
getting the error message "SQL server does not exist or access
denied.ConnectionOpen(Connect())" .
Why is this so? And how can I rectify the problem'If you use ping -a <ip address> does it bring back the correct name for the
server? If you ping SQLServer11 does it return the proper ip address? If
you are using NT authentication to register then try SQL authentication..
Verify that it is using port 1433 and that SQL Server is actually listening
on TCP/IP.
Rand
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