SQL Server 2000 Enterprise Manager stores information about registered servers in the following registry branch:

HKEY_USERS\<UserSID>\Software\Microsoft\Microsoft SQL Server\80\Tools\SQLEW\Registered Server X.

The registry values are binary and can not be transferred to another computer because they depend on user SID and computer where EM is placed. The SQL Server 2005 Server Management Studio no longer uses the registry to store this information, so that registered servers can be transferred using export/import feature.

However, both 2000 and 2005 versions continue to use another registry branch that is very important for transferring registered server’s information, which isn’t mentioned in this article. When you manage a number of instances on the different servers and different domains it is very convenient to create aliases for those servers and use them for server registration. Both 2000 Client Network Utility and 2005 SQL Server Configuration Manager store alias information in this registry branch:

HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\MSSQLServer\Client\ConnectTo.

So, if you import registered servers from 2000 EM to 2005 SMS on the same server, it works. On the other hand, if you use aliases and export registered servers from 2005 SMS, located on one server, to 2005 SMS, located on another server, the imported registered servers will appear on the SMS  “Registered Servers” window. However, you can’t connect to those servers, because the connection information is absent. In this case, you also need to import the registry branch that stores the alias properties.