Merge Replication from SQL 2008 R2 to SQL 2005 Express: SQL Server version (10.50) is not supported I'm setting up a (one way) pull, RMO merge replication via web sync from my main database (SQL Server 2008 R2) and clients running SQL Server 2005 Express or 2008 Express (I must support both). I've set up the publication to support SQL 2005. When syncing to SQL 2008 Express, all is fine. 

The problems arises when I use SQL 2005 Express. The error occurs on the first attempt at connecting. Sorry about the Norwegian text in the error message:

System.ApplicationException: [My custom text] ---&gt;  Microsoft.SqlServer.Management.Common.ConnectionFailureException: Failed to connect to server test-db01. ---&gt; Microsoft.SqlServer.Management.Common.ConnectionFailureException: This SQL Server version (10.50) is not supported.
   ved Microsoft.SqlServer.Management.Common.ConnectionManager.CheckServerVersion(ServerVersion version)
   ved Microsoft.SqlServer.Management.Common.ConnectionManager.InternalConnect(WindowsIdentity impersonatedIdentity)
   ved Microsoft.SqlServer.Management.Common.ConnectionManager.Connect()
   --- Slutten på sporingen av intern unntaksstakk ---
   ved Microsoft.SqlServer.Management.Common.ConnectionManager.Connect()
   ved Microsoft.SqlServer.Management.Common.ConnectionManager.PoolConnect()
   ved Microsoft.SqlServer.Management.Common.ConnectionManager.get_ServerVersion()
   ved Microsoft.SqlServer.Management.Common.ServerConnection.get_TrueName()
   ved Microsoft.SqlServer.Replication.ReplicationObject.CommonConstructor(ServerConnection connectionContext)
   ved Microsoft.SqlServer.Replication.ReplicationObject.set_ConnectionContext(ServerConnection value)
   ved Farry.FarryClients.FarryClientServices.FarryOfflineComponents.DbSync.MergeReplication.DropSubscription() i C:\Farry\Farry\FarryClients\FarryClientServices\FarryOfflineComponents\DbSync\MergeReplication.cs:linje 83
   --- Slutten på sporingen av intern unntaksstakk ---
   ved Farry.FarryClients.FarryClientServices.FarryOfflineComponents.DbSync.MergeReplication.DropSubscription() i C:\Farry\Farry\FarryClients\FarryClientServices\FarryOfflineComponents\DbSync\MergeReplication.cs:linje 129
   ved Farry.FarryClients.FarryClientServices.FarryNetClient.Offline.DbSyncManager.AddSubscription() i C:\Farry\Farry\FarryClients\FarryClientServices\FarryNetClient\Offline\DbSyncManager.cs:linje 142
   ved Farry.FarryClients.FarryClientServices.FarryNetClient.Offline.DbSyncManager.Work() i C:\Farry\Farry\FarryClients\FarryClientServices\FarryNetClient\Offline\DbSyncManager.cs:linje 181


As the publication is set up to support 2005, what must I remember (which I probably haven't) to make syncing to 2005 work?
Try to change setting,

Step 1: Launch the DFS Management Console (on the cluster node ‘PrimaryNode’).

Step 2: Click on the ‘New Replication Group…’ action.

Step 3: Select the type of replication group.

Step 4: Select the name and domain for the replication group.

Step 5: Specify the branch office file server (replication member)

Step 6: Select the folders to replicate from the branch office server.

Step 7: Specify the hub server (other replication member)

Step 8: Specify the path to the replicated folder on the hub server.

Step 9: Configure the replication schedule and bandwidth utilization.

then you apply and hope your problem will be solve.

http://www.techyv.com/questions/2008-r-2-replication-errors