MDAC 2.6 or later should not be installed on SQL Server 7.0 clusters

Do not install Microsoft Data Access Components (MDAC) 2.6 or later on any SQL Server 7.0 clustered nodes. If you install MDAC 2.6 or later on any node in the cluster, directly or through the installation of another program, it may cause a catastrophic failure of the SQL Server Agent or other SQL Server services.

To resolve this problem, you must recover your SQL Server computer. To do so, use one of the following methods. These methods are listed in the order of preference.

• Upgrade your existing installation to a SQL Server 2000 virtual server.
• Remove the SQL Server computer from the cluster, and then continue to use the SQL Server computer as a stand-alone server without cluster functionality.
• Format and reinstall by using the information in the following Microsoft Knowledge Base article:
  219264  (http://support.microsoft.com/kb/219264/ ) Order of installation for SQL Server 7.0 clustering setup

Note This issue can occur when Veritas' Backup Exec 9.0 for Windows Servers is installed on SQL Server 7.0 Clusters. For more information, see the Veritas Technote that is available at the following website: The third-party products that are discussed in this article are manufactured by companies that are independent of Microsoft. Microsoft makes no warranty, implied or otherwise, regarding the performance or reliability of these products.