What command are you using to test the name resolution?

C:\> Nslookup SQL_Virtual

Resolves both forward lookup and reverse lookup

C:\> NSlookup SQL_Virtual.ABC.COM

Resolves both forward lookup and reverse lookup

implies that name resolution is possibly not ok[/b]

I dont disagree. But, I am wondering why only for Windows Authentication in SQL Enterprise Manager and also in ODBC DSN configuration? The name resolution seems to be working fine while using SQL Authentication .

One thing to check on the client is the DNS search suffix list on the NIC advanced properties, ensure that any domains you need to search are listed here

I tried adding abc.com, but it did not help.