On my machine I have installed both SQL Server 2000 as SQL Server 2005.
On another machine SQL Server 2000 is installed.
I am able to connect to my local SQL Server 2000 Engine from within both
Enterprise Manager as SSMS.
Enterprise Manger also allows me to connect to the other machine, however
when I try to connect to it from SSMS I receive an error saying it cannot
connect.
In both cases I have used SQL Server authentication.

One possibility. On the client computer you can connect to the SQL Server
2000 server using Enterprise Manager. That's using the network settings of
the SQL Server 2000 Client Network Utility. And I presume TCP (or your
preferred protocol) is enabled.
But when you connect from the client with Management Studio, it will use the
network settings from the SQL Server Native Client, and perhaps TCP (or your
preferred protocol) is not enabled for your client. Using the SQL Server
Configuration Manager, on the client computer, check the SQL Server 2005
Native Client Configuration \ Client Protocols, and confirm that TCP/IP (or
your preferred protocol) is enabled. Try moving it up in the Order value so
your preferred protocol is selected first.
At any rate, I'm guessing that Enterprise Manager and Management Studio are
attempting different protocols.
The problem could also be caused by an Alias that is used by EM but not
configured for SSMS.
--
Rick Byham (MSFT)
This posting is provided "AS IS" with no warranties, and confers no rights.

"Ronald Bijlhouwer" <Ronald Bijlhouwer@discussions.microsoft.com> wrote in
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