Short story: after restoring a SqlExpress 2005 LOB db to a new server, the client application cannot connect anymore to the instance (invalid connection).
So I have a LOB db hosted on a sqlexpress 2005 server (to be retired) that has to be moved to a new server. I installed the same version LOB db on the new server: it installed the same sqlexpress 2005 engine (9.0.3042) and created a new empty db. I install the application on a workstation and establish a ODBC connection with the new server. So I have access to the new empty db, where I can start entering data. I then made a backup of the db on the old server using Management Studio / right-clic on db / backup / create new file / and save to a .bak file. In management studio on the new server, I restore the bakcup file to the new empty db using the Tasks / Restore / select .bak file. Restore runs without error.
But then the client workstation cannot connect anymore to the Instance hosting the restored file: ODBC connection is invalid.
I tried to detach the DB from the old server and then attach it to the new without success. Tried with different versions of SQL Express 2005 also without success. Do I need to restore also the system databases (master, model, msdb, tempdb), or proceed differently ?
Environment info: Old server = sbs2003 running Sqlexpress 2005 v.9.0.3042. New server = sbs2011 running Sqlexpress 2005 v9.0.3042 (has also Sql express 2008 R2 running for other instances (sharepoint, wsus).