Source computer: SQL server 2005 SP1
Remote computer : SQLEXPRESS  

When I try to register/connect with remote server (named instance) using sql
server management studio I am getting following error:

TITLE: New Server Registration
------------------------------
Testing the registered server failed. Verify the server name, login
credentials, and database, and then click Test again.
------------------------------
ADDITIONAL INFORMATION:
An error has occurred while establishing a connection to the server.  When
connecting to SQL Server 2005, this failure may be caused by the fact that
under the default settings SQL Server does not allow remote connections.
(provider: SQL Network Interfaces, error: 25 - Connection string is not
valid) (Microsoft SQL Server, Error: 87)

Thanks

Ontario, canada