Replicating Between Different Versions of SQL Server

If you currently use Microsoft® SQL Server™version 6.x in your application, SQL Server 7.0 offers you the choice of upgrading replication from version 6.x or implementing replication between the two versions. Both upgrading and implementing replication across different versions is subject to certain constraints.

Upgrading from SQL Server Version 6.x

When upgrading an installation of SQL Server from version 6.x to version 7.0, the following constraints apply to replication:

If the installation of SQL Server 6.5 already has replication enabled, the upgrade may fail if there are replicated transactions in the publishing database. You can determine the exact cause of failure by reviewing the text of the error message in Replication.err located in the specific directory for your upgrade.
You cannot upgrade the replication of the pubs sample database. The pubs database is re-created during the installation of SQL Server 7.0 and all replication information for the database is deleted.
The schedules for replication tasks that are being upgraded are reset to the default schedule. After the upgrade process is finished, you should reset the desired schedule for each task.
You cannot upgrade replication settings directly from SQL Server 6.0 to SQL Server 7.0. You must first upgrade your installation to SQL Server 6.5.

Replicating Between SQL Server Version 6.x and Version 7.0

SQL Server version 7.0 supports limited replication with SQL Server 6.x servers. The following combinations are supported:

Replication from a SQL Server 7.0 Publisher/Distributor (both the Publisher and Distributor are located on the same server) to a SQL Server 6.5 Subscriber.
However, you cannot use SQL Server 7.0 replication features that are not supported in SQL Server 6.5 (for example, table names greater than 30 characters and uniqueidentifier or Unicode data types).
Replication from a SQL Server 7.0 Publisher/Distributor to a SQL Server 6.0 Subscriber.
However, the SQL Server 6.0 Subscriber must be configured as an ODBC Subscriber and not as a native SQL Server Subscriber.
Replication from a SQL Server 6.5 Publisher/Distributor to a SQL Server 7.0 Subscriber.
Replication from a SQL Server 6.5 Publisher to a SQL Server 7.0 Distributor.

ANSI to OEM Replication

SQL Server 7.0 does not support replication between two servers with different code pages. If your application requires replication across languages, use Unicode data types.